1
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LaFleur A, Li H, Frank CE, Xu M, Cheng S, Wang Z, Butch NP, Zeljkovic I. Inhomogeneous high temperature melting and decoupling of charge density waves in spin-triplet superconductor UTe 2. Nat Commun 2024; 15:4456. [PMID: 38796494 PMCID: PMC11127989 DOI: 10.1038/s41467-024-48844-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Accepted: 05/15/2024] [Indexed: 05/28/2024] Open
Abstract
Charge, spin and Cooper-pair density waves have now been widely detected in exotic superconductors. Understanding how these density waves emerge - and become suppressed by external parameters - is a key research direction in condensed matter physics. Here we study the temperature and magnetic-field evolution of charge density waves in the rare spin-triplet superconductor candidate UTe2 using scanning tunneling microscopy/spectroscopy. We reveal that charge modulations composed of three different wave vectors gradually weaken in a spatially inhomogeneous manner, while persisting to surprisingly high temperatures of 10-12 K. We also reveal an unexpected decoupling of the three-component charge density wave state. Our observations match closely to the temperature scale potentially related to short-range magnetic correlations, providing a possible connection between density waves observed by surface probes and intrinsic bulk features. Importantly, charge density wave modulations become suppressed with magnetic field both below and above superconducting Tc in a comparable manner. Our work points towards an intimate connection between hidden magnetic correlations and the origin of the unusual charge density waves in UTe2.
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Affiliation(s)
| | - Hong Li
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Corey E Frank
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Muxian Xu
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Siyu Cheng
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Ziqiang Wang
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Nicholas P Butch
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Ilija Zeljkovic
- Department of Physics, Boston College, Chestnut Hill, MA, USA.
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2
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Awelewa S, Dzero M. Migdal-Eliashberg superconductivity in a Kondo lattice. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:325602. [PMID: 38663412 DOI: 10.1088/1361-648x/ad43a5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 04/25/2024] [Indexed: 05/18/2024]
Abstract
We apply the Migdal-Eliashberg theory of superconductivity to heavy-fermion and mixed valence materials. Specifically, we extend the Anderson lattice model to a case when there exists a strong coupling between itinerant electrons and lattice vibrations. Using the saddle-point approximation, we derive a set of coupled nonlinear equations which describe competition between the crossover to a heavy-fermion or mixed-valence regimes and conventional superconductivity. We find that superconductivity at strong coupling emerges on par with the development of the many-body coherence in a Kondo lattice. Superconductivity is gradually suppressed with the onset of the Kondo screening and for strong electron-phonon coupling the Kondo screening exhibits a characteristic re-entrant behavior. Even though for both weak and strong coupling limits the suppression of superconductivity is weaker in the mixed-valence regime compared to the local moment one, superconducting critical temperature still remains nonzero. In the weak coupling limit the onset of the many body coherence develops gradually, in the strong coupling limit it emerges abruptly in the mixed valence regime while in the local moment regime thef-electrons remain effectively decoupled from the conduction electrons. Possibility of experimental realization of these effects in Ce-based compounds is also discussed.
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Affiliation(s)
- Samuel Awelewa
- Department of Physics, Kent State University, Kent, OH 44242, United States of America
| | - Maxim Dzero
- Department of Physics, Kent State University, Kent, OH 44242, United States of America
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3
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Frank CE, Lewin SK, Saucedo Salas G, Czajka P, Hayes IM, Yoon H, Metz T, Paglione J, Singleton J, Butch NP. Orphan high field superconductivity in non-superconducting uranium ditelluride. Nat Commun 2024; 15:3378. [PMID: 38643147 PMCID: PMC11032386 DOI: 10.1038/s41467-024-47090-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/15/2024] [Indexed: 04/22/2024] Open
Abstract
Reentrant superconductivity is an uncommon phenomenon in which the destructive effects of magnetic field on superconductivity are mitigated, allowing a zero-resistance state to survive under conditions that would otherwise destroy it. Typically, the reentrant superconducting region derives from a zero-field parent superconducting phase. Here, we show that in UTe2 crystals extreme applied magnetic fields give rise to an unprecedented high-field superconductor that lacks a zero-field antecedent. This high-field orphan superconductivity exists at angles offset between 29o and 42o from the crystallographic b to c axes with applied fields between 37 T and 52 T. The stability of field-induced orphan superconductivity presented in this work defies both empirical precedent and theoretical explanation and demonstrates that high-field superconductivity can exist in an otherwise non-superconducting material.
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Affiliation(s)
- Corey E Frank
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA.
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA.
| | - Sylvia K Lewin
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Gicela Saucedo Salas
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Peter Czajka
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Ian M Hayes
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Hyeok Yoon
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Tristin Metz
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Johnpierre Paglione
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
- Canadian Institute for Advanced Research, Toronto, ON, M5G 1Z8, Canada
| | - John Singleton
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Nicholas P Butch
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA.
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA.
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4
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Li C, Wang Y, Liu K, Jiang D, Feng J, Wen T, Yue B, Zhou Y, Sun L, Wang Y. Superconductivity in Quasi-One-Dimensional Ferromagnet CrSbSe 3 under High Pressure. J Am Chem Soc 2024; 146:9688-9696. [PMID: 38427795 DOI: 10.1021/jacs.3c13503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
Nearly a decade has passed since the discovery of superconductivity in CrAs, but until now, the discovered structure types of chromium-based superconductors are still scanty. It is urgent to expand this family to decipher the interplay between magnetism and superconductivity penetratingly. Here, we report the observation of superconductivity in ferromagnet CrSbSe3 with a quasi-one-dimensional structure under high pressure. Under compression, CrSbSe3 undergoes an insulator-to-metal transition and sequential isostructural phase transitions accompanied by volume collapse. Superconductivity emerges at 32.8 GPa concomitant with metallization in CrSbSe3. A maximum superconducting transition temperature Tc of 7.7 K is achieved at 57.9 GPa benefiting from both the phonon softening and the enhanced p-d hybridization between Se and Cr in CrSbSe3. The discovery of superconductivity in CrSbSe3 expands the existing chromium-based superconductor family and sheds light on the search for concealed superconductivity in low-dimensional van der Waals materials.
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Affiliation(s)
- Chen Li
- School of Materials Science and Engineering, Peking University, Beijing 100871, China
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
| | - Yiming Wang
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
| | - Ke Liu
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
| | - Dequan Jiang
- School of Materials Science and Engineering, Peking University, Beijing 100871, China
| | - Jiajia Feng
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
| | - Ting Wen
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
| | - Binbin Yue
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
| | - Yazhou Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Liling Sun
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Yonggang Wang
- School of Materials Science and Engineering, Peking University, Beijing 100871, China
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100193, China
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5
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Gassner S, Weber CS, Claassen M. Light-induced switching between singlet and triplet superconducting states. Nat Commun 2024; 15:1776. [PMID: 38413590 PMCID: PMC10899631 DOI: 10.1038/s41467-024-45949-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 02/08/2024] [Indexed: 02/29/2024] Open
Abstract
While the search for topological triplet-pairing superconductivity has remained a challenge, recent developments in optically stabilizing metastable superconducting states suggest a new route to realizing this elusive phase. Here, we devise a testable theory of competing superconducting orders that permits ultrafast switching to an opposite-parity superconducting phase in centrosymmetric crystals with strong spin-orbit coupling. Using both microscopic and phenomenological models, we show that dynamical inversion symmetry breaking with a tailored light pulse can induce odd-parity (spin triplet) order parameter oscillations in a conventional even-parity (spin singlet) superconductor, which when driven strongly can send the system to a competing minimum in its free energy landscape. Our results provide new guiding principles for engineering unconventional electronic phases using light, suggesting a fundamentally non-equilibrium route toward realizing topological superconductivity.
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Affiliation(s)
- Steven Gassner
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - Clara S Weber
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Institut für Theorie der Statistischen Physik, RWTH Aachen and JARA - Fundamentals of Future Information Technology, D-52056, Aachen, Germany
| | - Martin Claassen
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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6
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Chajewski G, Kaczorowski D. Discovery of Magnetic Phase Transitions in Heavy-Fermion Superconductor CeRh_{2}As_{2}. PHYSICAL REVIEW LETTERS 2024; 132:076504. [PMID: 38427882 DOI: 10.1103/physrevlett.132.076504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 01/17/2024] [Indexed: 03/03/2024]
Abstract
We report on the specific heat studies performed on a new generation of CeRh_{2}As_{2} single crystals. Superior quality of the samples and dedicated experimental protocol allowed us to observe an antiferromagneticlike behavior in the normal state and to detect the first-order phase transition of magnetic origin within the superconducting state of the compound. Although in the available literature the physical behavior of CeRh_{2}As_{2} is most often described with the use of quadrupole density wave scenario, we propose an alternative explanation using analogies to antiferromagnetic heavy-fermion superconductors CeRhIn_{5} and Ce_{2}RhIn_{8}.
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Affiliation(s)
- Grzegorz Chajewski
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-422 Wrocław, Poland
| | - Dariusz Kaczorowski
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-422 Wrocław, Poland
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7
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Theuss F, Simarro GDLF, Shragai A, Grissonnanche G, Hayes IM, Saha S, Shishidou T, Chen T, Nakatsuji S, Ran S, Weinert M, Butch NP, Paglione J, Ramshaw BJ. Resonant Ultrasound Spectroscopy for Irregularly Shaped Samples and Its Application to Uranium Ditelluride. PHYSICAL REVIEW LETTERS 2024; 132:066003. [PMID: 38394590 DOI: 10.1103/physrevlett.132.066003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 08/22/2023] [Accepted: 01/11/2024] [Indexed: 02/25/2024]
Abstract
Resonant ultrasound spectroscopy (RUS) is a powerful technique for measuring the full elastic tensor of a given material in a single experiment. Previously, this technique was practically limited to regularly shaped samples such as rectangular parallelepipeds, spheres, and cylinders [W. M. Visscher et al. J. Acoust. Soc. Am. 90, 2154 (1991)JASMAN0001-496610.1121/1.401643]. We demonstrate a new method for determining the elastic moduli of irregularly shaped samples, extending the applicability of RUS to a much larger set of materials. We apply this new approach to the recently discovered unconventional superconductor UTe_{2} and provide its elastic tensor at both 300 and 4 kelvin.
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Affiliation(s)
- Florian Theuss
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | | | - Avi Shragai
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - Gael Grissonnanche
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - Ian M Hayes
- Quantum Materials Center, Department of Physics, University of Maryland, College Park, Maryland 20742, USA
| | - Shanta Saha
- Quantum Materials Center, Department of Physics, University of Maryland, College Park, Maryland 20742, USA
| | - Tatsuya Shishidou
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA
| | - Taishi Chen
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Satoru Nakatsuji
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Department of Physics, The University of Tokyo, Tokyo 113-0033, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
- Trans-scale Quantum Science Institute, University of Tokyo, Tokyo 113-0033, Japan
| | - Sheng Ran
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Michael Weinert
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA
| | - Nicholas P Butch
- Quantum Materials Center, Department of Physics, University of Maryland, College Park, Maryland 20742, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, USA
| | - Johnpierre Paglione
- Quantum Materials Center, Department of Physics, University of Maryland, College Park, Maryland 20742, USA
- Canadian Institute for Advanced Research, Toronto, Ontario, Canada
| | - B J Ramshaw
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
- Canadian Institute for Advanced Research, Toronto, Ontario, Canada
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8
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Suetsugu S, Shimomura M, Kamimura M, Asaba T, Asaeda H, Kosuge Y, Sekino Y, Ikemori S, Kasahara Y, Kohsaka Y, Lee M, Yanase Y, Sakai H, Opletal P, Tokiwa Y, Haga Y, Matsuda Y. Fully gapped pairing state in spin-triplet superconductor UTe 2. SCIENCE ADVANCES 2024; 10:eadk3772. [PMID: 38324692 PMCID: PMC10849587 DOI: 10.1126/sciadv.adk3772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/05/2024] [Indexed: 02/09/2024]
Abstract
The recently discovered superconductor UTe2 is a promising candidate for spin-triplet superconductors, but the symmetry of the superconducting order parameter remains highly controversial. Here, we determine the superconducting gap structure by the thermal conductivity of ultraclean UTe2 single crystals. We find that the a-axis thermal conductivity divided by temperature κ/T in zero-temperature limit is vanishingly small for both magnetic field H‖a and H‖c axes up to H/Hc2 ∼ 0.2, demonstrating the absence of nodes around the a axis contrary to the previous belief. The present results, combined with the reduction of nuclear magnetic resonance Knight shift, indicate that the superconducting order parameter belongs to the isotropic Au representation with a fully gapped pairing state, analogous to the B phase of superfluid 3He. These findings reveal that UTe2 is likely to be a long-sought three-dimensional strong topological superconductor, hosting helical Majorana surface states on any crystal plane.
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Affiliation(s)
- Shota Suetsugu
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | | | | | - Tomoya Asaba
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Hiroto Asaeda
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Yuki Kosuge
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Yuki Sekino
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Shun Ikemori
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Yuichi Kasahara
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Yuhki Kohsaka
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Minhyea Lee
- Department of Physics, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Youichi Yanase
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Hironori Sakai
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Petr Opletal
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Yoshifumi Tokiwa
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Yoshinori Haga
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Yuji Matsuda
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
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9
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Silber I, Mathimalar S, Mangel I, Nayak AK, Green O, Avraham N, Beidenkopf H, Feldman I, Kanigel A, Klein A, Goldstein M, Banerjee A, Sela E, Dagan Y. Two-component nematic superconductivity in 4Hb-TaS 2. Nat Commun 2024; 15:824. [PMID: 38280890 PMCID: PMC10821864 DOI: 10.1038/s41467-024-45169-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/15/2024] [Indexed: 01/29/2024] Open
Abstract
Most superconductors have an isotropic, single component order parameter and are well described by the standard (BCS) theory for superconductivity. Unconventional, multiple-component superconductors are exceptionally rare and are much less understood. Here, we combine scanning tunneling microscopy and angle-resolved macroscopic transport for studying the candidate chiral superconductor, 4Hb-TaS2. We reveal quasi-periodic one-dimensional modulations in the tunneling conductance accompanied by two-fold symmetric superconducting critical field. The strong modulation of the in-plane critical field, Hc2, points to a nematic, unconventional order parameter. However, the imaged vortex core is isotropic at low temperatures. We suggest a model that reconciles this apparent discrepancy and takes into account previously observed spontaneous time-reversal symmetry breaking at low temperatures. The model describes a competition between a dominating chiral superconducting order parameter and a nematic one. The latter emerges close to the normal phase. Our results strongly support the existence of two-component superconductivity in 4Hb-TaS2 and can provide valuable insights into other systems with coexistent charge order and superconductivity.
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Affiliation(s)
- I Silber
- School of Physics and Astronomy, Tel - Aviv University, Tel Aviv, 69978, Israel
| | - S Mathimalar
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - I Mangel
- Physics Department, Technion-Israel Institute of Technology, Haifa, 32000, Israel
| | - A K Nayak
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - O Green
- School of Physics and Astronomy, Tel - Aviv University, Tel Aviv, 69978, Israel
| | - N Avraham
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - H Beidenkopf
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - I Feldman
- Physics Department, Technion-Israel Institute of Technology, Haifa, 32000, Israel
| | - A Kanigel
- Physics Department, Technion-Israel Institute of Technology, Haifa, 32000, Israel
| | - A Klein
- Department of Physics, Faculty of Natural Sciences, Ariel University, Ariel, 40700, Israel
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - M Goldstein
- School of Physics and Astronomy, Tel - Aviv University, Tel Aviv, 69978, Israel
| | - A Banerjee
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel
| | - E Sela
- School of Physics and Astronomy, Tel - Aviv University, Tel Aviv, 69978, Israel
| | - Y Dagan
- School of Physics and Astronomy, Tel - Aviv University, Tel Aviv, 69978, Israel.
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10
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Kitamura T, Daido A, Yanase Y. Spin-Triplet Superconductivity from Quantum-Geometry-Induced Ferromagnetic Fluctuation. PHYSICAL REVIEW LETTERS 2024; 132:036001. [PMID: 38307086 DOI: 10.1103/physrevlett.132.036001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 11/19/2023] [Accepted: 11/29/2023] [Indexed: 02/04/2024]
Abstract
We show that quantum geometry induces ferromagnetic fluctuation resulting in spin-triplet superconductivity. The criterion for ferromagnetic fluctuation is clarified by analyzing contributions from the effective mass and quantum geometry. When the non-Kramers band degeneracy is present near the Fermi surface, the Fubini-Study quantum metric strongly favors ferromagnetic fluctuation. Solving the linearized gap equation with the effective interaction obtained by the random phase approximation, we show that the spin-triplet superconductivity is mediated by quantum-geometry-induced ferromagnetic fluctuation.
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Affiliation(s)
- Taisei Kitamura
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Akito Daido
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Youichi Yanase
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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11
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Wang S, Zhong M, Liu H, Ju M. Coexistence of topological node surface and Dirac fermions in phonon-mediated superconductor YB 2C 2. Phys Chem Chem Phys 2024; 26:1454-1461. [PMID: 38113107 DOI: 10.1039/d3cp03678b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The interaction between nontrivial topology and superconductivity in condensed matter physics has attracted tremendous research interest as it could give rise to exotic phenomena. Herein, based on first-principles calculations, we investigate the electronic structures, mechanical properties, topological properties, dynamic stability, electron-phonon coupling (EPC), and superconducting properties of the synthesized real material YB2C2. It is a tetragonal structure with P4/mbm symmetry and exhibits excellent stability. The calculated electronic band structures reveal that a zero-dimension (0D) Dirac point and two-dimensional (2D) nodal surface coexist near the Fermi level. A spin-orbit coupling (SOC) Dirac point with the topological Fermi arc is observed on the (001) surface. These nodal surfaces are protected by a two-fold screw axis and time-reversal symmetry. Based on the Bardeen-Cooper-Schrieffer theory, the superconducting transition temperature (Tc) in the range 1.25-4.45 K with different Coulomb repulsion constant μ* for YB2C2 is estimated to be consistent with previous experimental results. In addition, the EPC is mainly from the coupling between the dx2-y2 and dz2 orbitals of the Y atom and low-energy phonon modes. The presence of superconductivity and nontrivial topological surface state in YB2C2 suggests that it may be a candidate material for topological superconductors.
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Affiliation(s)
- Siqi Wang
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Mingmin Zhong
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Haibo Liu
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
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12
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Eaton AG, Weinberger TI, Popiel NJM, Wu Z, Hickey AJ, Cabala A, Pospíšil J, Prokleška J, Haidamak T, Bastien G, Opletal P, Sakai H, Haga Y, Nowell R, Benjamin SM, Sechovský V, Lonzarich GG, Grosche FM, Vališka M. Quasi-2D Fermi surface in the anomalous superconductor UTe 2. Nat Commun 2024; 15:223. [PMID: 38172154 PMCID: PMC10764345 DOI: 10.1038/s41467-023-44110-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 11/30/2023] [Indexed: 01/05/2024] Open
Abstract
The heavy fermion paramagnet UTe2 exhibits numerous characteristics of spin-triplet superconductivity. Efforts to understand the microscopic details of this exotic superconductivity have been impeded by uncertainty regarding the underlying electronic structure. Here we directly probe the Fermi surface of UTe2 by measuring magnetic quantum oscillations in pristine quality crystals. We find an angular profile of quantum oscillatory frequency and amplitude that is characteristic of a quasi-2D Fermi surface, which we find is well described by two cylindrical Fermi sheets of electron- and hole-type respectively. Additionally, we find that both cylindrical Fermi sheets possess considerable undulation but negligible small-scale corrugation, which may allow for their near-nesting and therefore promote magnetic fluctuations that enhance the triplet pairing mechanism. Importantly, we find no evidence for the presence of any 3D Fermi surface sections. Our results place strong constraints on the possible symmetry of the superconducting order parameter in UTe2.
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Affiliation(s)
- A G Eaton
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK.
| | - T I Weinberger
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - N J M Popiel
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Z Wu
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - A J Hickey
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - A Cabala
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
| | - J Pospíšil
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
| | - J Prokleška
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
| | - T Haidamak
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
| | - G Bastien
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
| | - P Opletal
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - H Sakai
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - Y Haga
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - R Nowell
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - S M Benjamin
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - V Sechovský
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
| | - G G Lonzarich
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - F M Grosche
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - M Vališka
- Charles University, Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Ke Karlovu 5, Prague 2, 121 16, Czech Republic
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13
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Helm T, Kimata M, Sudo K, Miyata A, Stirnat J, Förster T, Hornung J, König M, Sheikin I, Pourret A, Lapertot G, Aoki D, Knebel G, Wosnitza J, Brison JP. Field-induced compensation of magnetic exchange as the possible origin of reentrant superconductivity in UTe 2. Nat Commun 2024; 15:37. [PMID: 38167667 PMCID: PMC10761692 DOI: 10.1038/s41467-023-44183-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 12/04/2023] [Indexed: 01/05/2024] Open
Abstract
The potential spin-triplet heavy-fermion superconductor UTe2 exhibits signatures of multiple distinct superconducting phases. For field aligned along the b axis, a metamagnetic transition occurs at μ0Hm ≈ 35 T. It is associated with magnetic fluctuations that may be beneficial for the field-reinforced superconductivity surviving up to Hm. Once the field is tilted away from the b towards the c axis, a reentrant superconducting phase emerges just above Hm. In order to better understand this remarkably field-resistant superconducting phase, we conducted magnetic-torque and magnetotransport measurements in pulsed magnetic fields. We determine the record-breaking upper critical field of μ0Hc2 ≈ 73 T and its evolution with angle. Furthermore, the normal-state Hall effect experiences a drastic suppression indicative of a reduced band polarization above Hm in the angular range around 30° caused by a partial compensation between the applied field and an exchange field. This promotes the Jaccarino-Peter effect as a likely mechanism for the reentrant superconductivity above Hm.
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Affiliation(s)
- Toni Helm
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany.
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany.
| | - Motoi Kimata
- Institute for Materials Research, Tohoku University, Sendai, Miyagi, 980-8577, Japan
| | - Kenta Sudo
- Institute for Materials Research, Tohoku University, Sendai, Miyagi, 980-8577, Japan
| | - Atsuhiko Miyata
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Julia Stirnat
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
| | - Tobias Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Jacob Hornung
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
| | - Markus König
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - Ilya Sheikin
- Laboratoire National des Champs Magnétiques Intenses (LNCMI-EMFL), CNRS, UGA, 38042, Grenoble, France
| | - Alexandre Pourret
- Univ. Grenoble Alpes, CEA, Grenoble-INP, IRIG, PHELIQS, 38000, Grenoble, France
| | - Gerard Lapertot
- Univ. Grenoble Alpes, CEA, Grenoble-INP, IRIG, PHELIQS, 38000, Grenoble, France
| | - Dai Aoki
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki, 311-1313, Japan
| | - Georg Knebel
- Univ. Grenoble Alpes, CEA, Grenoble-INP, IRIG, PHELIQS, 38000, Grenoble, France
| | - Joachim Wosnitza
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
| | - Jean-Pascal Brison
- Univ. Grenoble Alpes, CEA, Grenoble-INP, IRIG, PHELIQS, 38000, Grenoble, France
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14
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Schönemann R, Rosa PFS, Thomas SM, Lai Y, Nguyen DN, Singleton J, Brosha EL, McDonald RD, Zapf V, Maiorov B, Jaime M. Sudden adiabaticity signals reentrant bulk superconductivity in UTe 2. PNAS NEXUS 2024; 3:pgad428. [PMID: 38234583 PMCID: PMC10791595 DOI: 10.1093/pnasnexus/pgad428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 11/27/2023] [Indexed: 01/19/2024]
Abstract
There has been a recent surge of interest in UTe2 due to its unconventional magnetic field (H)-reinforced spin-triplet superconducting phases persisting at fields far above the simple Pauli limit for H ∥ [ 010 ] . Magnetic fields in excess of 35 T then induce a field-polarized magnetic state via a first-order-like phase transition. More controversially, for field orientations close to H ∥ [ 011 ] and above 40 T, electrical resistivity measurements suggest that a further superconducting state may exist. However, no Meissner effect or thermodynamic evidence exists to date for this phase making it difficult to exclude alternative scenarios. In this paper, we describe a study using thermal, electrical, and magnetic probes in magnetic fields of up to 55 T applied between the [010] (b) and [001] (c) directions. Our MHz conductivity data reveal the field-induced state of low or vanishing electrical resistance; our simultaneous magnetocaloric effect measurements (i.e. changes in sample temperature due to changing magnetic field) show the first definitive evidence for adiabaticity and thermal behavior characteristic of bulk field-induced superconductivity.
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Affiliation(s)
- Rico Schönemann
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | | | - Sean M Thomas
- MPA-Q, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - You Lai
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Doan N Nguyen
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - John Singleton
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Eric L Brosha
- MPA-11, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Ross D McDonald
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Vivien Zapf
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Boris Maiorov
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Marcelo Jaime
- MPA-MAGLAB, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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15
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Watanabe Y, Miura A, Moriyoshi C, Yamashita A, Mizuguchi Y. Observation of superconductivity and enhanced upper critical field of η-carbide-type oxide Zr 4Pd 2O. Sci Rep 2023; 13:22458. [PMID: 38105267 PMCID: PMC10725861 DOI: 10.1038/s41598-023-49707-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023] Open
Abstract
We report the first observation of bulk superconductivity of a η-carbide-type oxide Zr4Pd2O. The crystal structure and the superconducting properties were studied through synchrotron X-ray diffraction, magnetization, electrical resistivity, and specific heat measurement. The superconducting transition was observed at Tc = 2.73 K. Our measurement revealed that the η-carbide-type oxide superconductor Zr4Pd2O shows an enhanced upper critical field μ0Hc2(0) = 6.72 T, which violates the Pauli-Clogston limit μ0HP = 5.29 T. On the other hand, we found that the enhanced upper critical field is absent in a Rh analogue Zr4Rh2O. The large μ0Hc2(0) of Zr4Pd2O would be raised from strong spin-orbit coupling with Pd-4d electrons. The discovery of new superconducting properties for Zr4Pd2O would shed light on the further development of η-carbide-type oxide superconductors.
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Affiliation(s)
- Yuto Watanabe
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo, 192-0397, Japan.
| | - Akira Miura
- Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, 060-8628, Japan
| | - Chikako Moriyoshi
- Graduate School of Advanced Science and Engineering, Hiroshima University, Higashihiroshima, Hiroshima, 739-8526, Japan
| | - Aichi Yamashita
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo, 192-0397, Japan
| | - Yoshikazu Mizuguchi
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo, 192-0397, Japan.
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16
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Chiang CC, Lee HC, Lin SC, Qu D, Chu MW, Chen CD, Chien CL, Huang SY. Unequivocal Identification of Spin-Triplet and Spin-Singlet Superconductors with Upper Critical Field and Flux Quantization. PHYSICAL REVIEW LETTERS 2023; 131:236003. [PMID: 38134800 DOI: 10.1103/physrevlett.131.236003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 11/13/2023] [Indexed: 12/24/2023]
Abstract
Spin-triplet superconductors play central roles in Majorana physics and quantum computing but are difficult to identify. We show the methods of kink-point upper critical field and flux quantization in superconducting rings can unequivocally identify spin-singlet, spin-triplet in centrosymmetric superconductors, and singlet-triplet admixture in noncentrosymmetric superconductors, as realized in γ-BiPd, β-Bi_{2}Pd, and α-BiPd, respectively. Our findings are essential for identifying triplet superconductors and exploring their quantum properties.
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Affiliation(s)
- C C Chiang
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
- Willian H. Miller III Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - H C Lee
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - S C Lin
- Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
| | - D Qu
- Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
- Center of Atomic Initiatives for New Materials, National Taiwan University, Taipei 10617, Taiwan
| | - M W Chu
- Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
- Center of Atomic Initiatives for New Materials, National Taiwan University, Taipei 10617, Taiwan
| | - C D Chen
- Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
| | - C L Chien
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
- Willian H. Miller III Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - S Y Huang
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
- Center of Atomic Initiatives for New Materials, National Taiwan University, Taipei 10617, Taiwan
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17
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Tokunaga Y, Sakai H, Kambe S, Opletal P, Tokiwa Y, Haga Y, Kitagawa S, Ishida K, Aoki D, Knebel G, Lapertot G, Krämer S, Horvatić M. Longitudinal Spin Fluctuations Driving Field-Reinforced Superconductivity in UTe_{2}. PHYSICAL REVIEW LETTERS 2023; 131:226503. [PMID: 38101342 DOI: 10.1103/physrevlett.131.226503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 09/29/2023] [Accepted: 10/18/2023] [Indexed: 12/17/2023]
Abstract
Our measurements of ^{125}Te NMR relaxations reveal an enhancement of electronic spin fluctuations above μ_{0}H^{*}∼15 T, leading to their divergence in the vicinity of the metamagnetic transition at μ_{0}H_{m}≈35 T, below which field-reinforced superconductivity appears when a magnetic field (H) is applied along the crystallographic b axis. The NMR data evidence that these fluctuations are dominantly longitudinal, providing a key to understanding the peculiar superconducting phase diagram in H∥b, where such fluctuations enhance the pairing interactions.
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Affiliation(s)
- Y Tokunaga
- ASRC, Japan Atomic Energy Agency Tokai, Ibaraki 319-1195, Japan
| | - H Sakai
- ASRC, Japan Atomic Energy Agency Tokai, Ibaraki 319-1195, Japan
| | - S Kambe
- ASRC, Japan Atomic Energy Agency Tokai, Ibaraki 319-1195, Japan
| | - P Opletal
- ASRC, Japan Atomic Energy Agency Tokai, Ibaraki 319-1195, Japan
| | - Y Tokiwa
- ASRC, Japan Atomic Energy Agency Tokai, Ibaraki 319-1195, Japan
| | - Y Haga
- ASRC, Japan Atomic Energy Agency Tokai, Ibaraki 319-1195, Japan
| | - S Kitagawa
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - K Ishida
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - D Aoki
- IMR, Tohoku University, Ibaraki 311-1313, Japan
- Université Grenoble Alpes, CEA, Grenoble-INP, IRIG, Pheliqs, 38000 Grenoble, France
| | - G Knebel
- Université Grenoble Alpes, CEA, Grenoble-INP, IRIG, Pheliqs, 38000 Grenoble, France
| | - G Lapertot
- Université Grenoble Alpes, CEA, Grenoble-INP, IRIG, Pheliqs, 38000 Grenoble, France
| | - S Krämer
- Laboratoire National des Champs Magnétiques Intenses, LNCMI-CNRS (UPR3228), EMFL, Université Grenoble Alpes, UPS and INSA Toulouse, Boîte Postale 166, 38042 Grenoble Cedex 9, France
| | - M Horvatić
- Laboratoire National des Champs Magnétiques Intenses, LNCMI-CNRS (UPR3228), EMFL, Université Grenoble Alpes, UPS and INSA Toulouse, Boîte Postale 166, 38042 Grenoble Cedex 9, France
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18
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Azari N, Yakovlev M, Rye N, Dunsiger SR, Sundar S, Bordelon MM, Thomas SM, Thompson JD, Rosa PFS, Sonier JE. Absence of Spontaneous Magnetic Fields due to Time-Reversal Symmetry Breaking in Bulk Superconducting UTe_{2}. PHYSICAL REVIEW LETTERS 2023; 131:226504. [PMID: 38101387 DOI: 10.1103/physrevlett.131.226504] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 10/18/2023] [Indexed: 12/17/2023]
Abstract
We have investigated the low-temperature local magnetic properties in the bulk of molten salt-flux (MSF)-grown single crystals of the candidate odd-parity superconductor UTe_{2} by zero-field muon spin relaxation (μSR). In contrast to previous μSR studies of UTe_{2} single crystals grown by a chemical vapor transport method, we find no evidence of magnetic clusters or electronic moments fluctuating slow enough to cause a discernible relaxation of the zero-field μSR asymmetry spectrum. Consequently, our measurements on MSF-grown single crystals rule out the generation of spontaneous magnetic fields in the bulk that would occur near impurities or lattice defects if the superconducting state of UTe_{2} breaks time-reversal symmetry. This result suggests that UTe_{2} is characterized by a single-component superconducting order parameter.
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Affiliation(s)
- N Azari
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - M Yakovlev
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - N Rye
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - S R Dunsiger
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
- Centre for Molecular and Materials Science, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - S Sundar
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - M M Bordelon
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S M Thomas
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J D Thompson
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - P F S Rosa
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J E Sonier
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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19
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Li G, Li M, Zhou X, Gao HJ. Toward large-scale, ordered and tunable Majorana-zero-modes lattice on iron-based superconductors. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 87:016501. [PMID: 37963402 DOI: 10.1088/1361-6633/ad0c5c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 11/14/2023] [Indexed: 11/16/2023]
Abstract
Majorana excitations are the quasiparticle analog of Majorana fermions in solid materials. Typical examples are the Majorana zero modes (MZMs) and the dispersing Majorana modes. When probed by scanning tunneling spectroscopy, the former manifest as a pronounced conductance peak locating precisely at zero-energy, while the latter behaves as constant or slowly varying density of states. The MZMs obey non-abelian statistics and are believed to be building blocks for topological quantum computing, which is highly immune to the environmental noise. Existing MZM platforms include hybrid structures such as topological insulator, semiconducting nanowire or 1D atomic chains on top of a conventional superconductor, and single materials such as the iron-based superconductors (IBSs) and 4Hb-TaS2. Very recently, ordered and tunable MZM lattice has also been realized in IBS LiFeAs, providing a scalable and applicable platform for future topological quantum computation. In this review, we present an overview of the recent local probe studies on MZMs. Classified by the material platforms, we start with the MZMs in the iron-chalcogenide superconductors where FeTe0.55Se0.45and (Li0.84Fe0.16)OHFeSe will be discussed. We then review the Majorana research in the iron-pnictide superconductors as well as other platforms beyond the IBSs. We further review recent works on ordered and tunable MZM lattice, showing that strain is a feasible tool to tune the topological superconductivity. Finally, we give our summary and perspective on future Majorana research.
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Affiliation(s)
- Geng Li
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Hefei National Laboratory, Hefei 230088, People's Republic of China
| | - Meng Li
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Xingtai Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Hong-Jun Gao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
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20
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Lewin SK, Frank CE, Ran S, Paglione J, Butch NP. A review of UTe 2at high magnetic fields. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 86:114501. [PMID: 37729901 DOI: 10.1088/1361-6633/acfb93] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 09/20/2023] [Indexed: 09/22/2023]
Abstract
Uranium ditelluride (UTe2) is recognized as a host material to unconventional spin-triplet superconductivity, but it also exhibits a wealth of additional unusual behavior at high magnetic fields. One of the most prominent signatures of the unconventional superconductivity is a large and anisotropic upper critical field that exceeds the paramagnetic limit. This superconductivity survives to 35 T and is bounded by a discontinuous magnetic transition, which itself is also field-direction-dependent. A different, reentrant superconducting phase emerges only on the high-field side of the magnetic transition, in a range of angles between the crystallographicbandcaxes. This review discusses the current state of knowledge of these high-field phases, the high-field behavior of the heavy fermion normal state, and other phases that are stabilized by applied pressure.
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Affiliation(s)
- Sylvia K Lewin
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, United States of America
- Department of Physics, Quantum Materials Center, University of Maryland, College Park, MD, United States of America
| | - Corey E Frank
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, United States of America
- Department of Physics, Quantum Materials Center, University of Maryland, College Park, MD, United States of America
| | - Sheng Ran
- Department of Physics, Washington University in St. Louis, St. Louis, MO, United States of America
| | - Johnpierre Paglione
- Department of Physics, Quantum Materials Center, University of Maryland, College Park, MD, United States of America
| | - Nicholas P Butch
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, United States of America
- Department of Physics, Quantum Materials Center, University of Maryland, College Park, MD, United States of America
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21
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Ao L, Huang J, Qin F, Li Z, Ideue T, Akhtari K, Chen P, Bi X, Qiu C, Huang D, Chen L, Belosludov RV, Gou H, Ren W, Nojima T, Iwasa Y, Bahramy MS, Yuan H. Valley-dimensionality locking of superconductivity in cubic phosphides. SCIENCE ADVANCES 2023; 9:eadf6758. [PMID: 37683003 PMCID: PMC10491139 DOI: 10.1126/sciadv.adf6758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 08/08/2023] [Indexed: 09/10/2023]
Abstract
Two-dimensional superconductivity is primarily realized in atomically thin layers through extreme exfoliation, epitaxial growth, or interfacial gating. Apart from their technical challenges, these approaches lack sufficient control over the Fermiology of superconducting systems. Here, we offer a Fermiology-engineering approach, allowing us to desirably tune the coherence length of Cooper pairs and the dimensionality of superconducting states in arsenic phosphides AsxP1-x under hydrostatic pressure. We demonstrate how this turns these compounds into tunable two-dimensional superconductors with a dome-shaped phase diagram even in the bulk limit. This peculiar behavior is shown to result from an unconventional valley-dimensionality locking mechanism, driven by a delicate competition between three-dimensional hole-type and two-dimensional electron-type energy pockets spatially separated in momentum space. The resulting dimensionality crossover is further discussed to be systematically controllable by pressure and stoichiometry tuning. Our findings pave a unique way to realize and control superconducting phases with special pairing and dimensional orders.
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Affiliation(s)
- Lingyi Ao
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Junwei Huang
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Feng Qin
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Zeya Li
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Toshiya Ideue
- Quantum-Phase Electronic Center and Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
- Institute for Solid State Physics, The University of Tokyo, Chiba 277-8581, Japan
| | - Keivan Akhtari
- Department of Physics, University of Kurdistan, Sanandaj 416, Iran
| | - Peng Chen
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Xiangyu Bi
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Caiyu Qiu
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
| | - Dajian Huang
- Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China
| | - Long Chen
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | | | - Huiyang Gou
- Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China
| | - Wencai Ren
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Tsutomu Nojima
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Yoshihiro Iwasa
- Quantum-Phase Electronic Center and Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
- RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
| | - Mohammad Saeed Bahramy
- Department of Physics and Astronomy, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Hongtao Yuan
- National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210000, China
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22
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Yang CK, Lee CH. Exchange interaction for the triplet superconductor UTe 2. Sci Rep 2023; 13:13995. [PMID: 37634046 PMCID: PMC10460447 DOI: 10.1038/s41598-023-41376-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 08/25/2023] [Indexed: 08/28/2023] Open
Abstract
UTe2 is one triplet superconductor that defies conventional relation between ferromagnetism and superconductivity. Our search for a theoretical explanation starts with one spin-triplet state of two electrons and construct a two-particle exchange interaction that favors the formation of Cooper pairs under the configuration. A modified application of the Bardeen-Cooper-Schrieffer (BCS) theory using parameters derived from ab-initio density functional calculations for electrons and phonons enables us to derive the critical temperature of 1.64 K and an average superconducting gap of 0.25 meV at 0 K. We extend the investigation further into the superconductivity under pressure, showing how Tc and the gap of UTe2 change under compression in ways that are consistent with the results of experiment.
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Affiliation(s)
- Chih-Kai Yang
- Graduate Institute of Applied Physics, National Chengchi University, Taipei, Taiwan, Republic of China.
| | - Chi-Hsuan Lee
- Graduate Institute of Applied Physics, National Chengchi University, Taipei, Taiwan, Republic of China
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23
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Mandal M, Drucker NC, Siriviboon P, Nguyen T, Boonkird A, Lamichhane TN, Okabe R, Chotrattanapituk A, Li M. Topological Superconductors from a Materials Perspective. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2023; 35:6184-6200. [PMID: 37637011 PMCID: PMC10448998 DOI: 10.1021/acs.chemmater.3c00713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 07/12/2023] [Indexed: 08/29/2023]
Abstract
Topological superconductors (TSCs) have garnered significant research and industry attention in the past two decades. By hosting Majorana bound states which can be used as qubits that are robust against local perturbations, TSCs offer a promising platform toward (nonuniversal) topological quantum computation. However, there has been a scarcity of TSC candidates, and the experimental signatures that identify a TSC are often elusive. In this Perspective, after a short review of the TSC basics and theories, we provide an overview of the TSC materials candidates, including natural compounds and synthetic material systems. We further introduce various experimental techniques to probe TSCs, focusing on how a system is identified as a TSC candidate and why a conclusive answer is often challenging to draw. We conclude by calling for new experimental signatures and stronger computational support to accelerate the search for new TSC candidates.
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Affiliation(s)
- Manasi Mandal
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Nuclear Science and Engineering, MIT, Cambridge, Massachusetts 02139, United States
| | - Nathan C. Drucker
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- School
of Engineering and Applied Sciences, Harvard
University, Cambridge, Massachusetts 02138, United States
| | - Phum Siriviboon
- Department
of Physics, MIT, Cambridge, Massachusetts 02139, United States
| | - Thanh Nguyen
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Nuclear Science and Engineering, MIT, Cambridge, Massachusetts 02139, United States
| | - Artittaya Boonkird
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Nuclear Science and Engineering, MIT, Cambridge, Massachusetts 02139, United States
| | - Tej Nath Lamichhane
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Nuclear Science and Engineering, MIT, Cambridge, Massachusetts 02139, United States
| | - Ryotaro Okabe
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Chemistry, MIT, Cambridge, Massachusetts 02139, United States
| | - Abhijatmedhi Chotrattanapituk
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Electrical Engineering and Computer Science, MIT, Cambridge, Massachusetts 02139, United States
| | - Mingda Li
- Quantum
Measurement Group, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Nuclear Science and Engineering, MIT, Cambridge, Massachusetts 02139, United States
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24
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Kinjo K, Fujibayashi H, Matsumura H, Hori F, Kitagawa S, Ishida K, Tokunaga Y, Sakai H, Kambe S, Nakamura A, Shimizu Y, Homma Y, Li D, Honda F, Aoki D. Superconducting spin reorientation in spin-triplet multiple superconducting phases of UTe 2. SCIENCE ADVANCES 2023; 9:eadg2736. [PMID: 37506206 PMCID: PMC10381943 DOI: 10.1126/sciadv.adg2736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 06/23/2023] [Indexed: 07/30/2023]
Abstract
Superconducting (SC) state has spin and orbital degrees of freedom, and spin-triplet superconductivity shows multiple SC phases because of the presence of these degrees of freedom. However, the observation of spin-direction rotation occurring inside the SC state (SC spin rotation) has hardly been reported. Uranium ditelluride, a recently found topological superconductor, exhibits various SC phases under pressure: SC state at ambient pressure (SC1), high-temperature SC state above 0.5 gigapascal (SC2), and low-temperature SC state above 0.5 gigapascal (SC3). We performed nuclear magnetic resonance (NMR) and ac susceptibility measurements on a single-crystal uranium ditelluride. The b axis spin susceptibility remains unchanged in SC2, unlike in SC1, and decreases below the SC2-SC3 transition with spin modulation. These unique properties in SC3 arise from the coexistence of two SC order parameters. Our NMR results confirm spin-triplet superconductivity with SC spin parallel to b axis in SC2 and unveil the remaining of spin degrees of freedom in SC uranium ditelluride.
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Affiliation(s)
- Katsuki Kinjo
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Hiroki Fujibayashi
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Hiroki Matsumura
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Fumiya Hori
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Shunsaku Kitagawa
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Kenji Ishida
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yo Tokunaga
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Hironori Sakai
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Shinsaku Kambe
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Ai Nakamura
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
| | - Yusei Shimizu
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
| | - Yoshiya Homma
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
| | - Dexin Li
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
| | - Fuminori Honda
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
- Central Institute of Radioisotope Science and Safety, Kyushu University, Fukuoka 819-0395, Japan
| | - Dai Aoki
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
- University Grenoble Alpes, CEA, Grenoble INP, IRIG, PHELIQS, F-38000 Grenoble, France
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25
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Broyles C, Rehfuss Z, Siddiquee H, Zhu JA, Zheng K, Nikolo M, Graf D, Singleton J, Ran S. Revealing a 3D Fermi Surface Pocket and Electron-Hole Tunneling in UTe_{2} with Quantum Oscillations. PHYSICAL REVIEW LETTERS 2023; 131:036501. [PMID: 37540859 DOI: 10.1103/physrevlett.131.036501] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 08/06/2023]
Abstract
Spin triplet superconductor UTe_{2} is widely believed to host a quasi-two-dimensional Fermi surface, revealed by first-principles calculations, photoemission, and quantum oscillation measurements. An outstanding question still remains as to the existence of a three-dimensional Fermi surface pocket, which is crucial for our understanding of the exotic superconducting and topological properties of UTe_{2}. This 3D Fermi surface pocket appears in various theoretical models with different physics origins, but has not been unambiguously detected in experiment. Here for the first time we provide concrete evidence for a relatively isotropic, small Fermi surface pocket of UTe_{2} via quantum oscillation measurements. In addition, we observed high frequency quantum oscillations corresponding to electron-hole tunneling between adjacent electron and hole pockets. The coexistence of 2D and 3D Fermi surface pockets, as well as the breakdown orbits, provide a test bed for theoretical models and aid the realization of a unified understanding of the superconducting state of UTe_{2} from the first-principles approach.
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Affiliation(s)
- Christopher Broyles
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Zack Rehfuss
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Hasan Siddiquee
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Jiahui Althena Zhu
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Kaiwen Zheng
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Martin Nikolo
- Department of Physics, Saint Louis University, St. Louis, Missouri 63103, USA
| | - David Graf
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - John Singleton
- National High Magnetic Field Laboratory, Pulse Field Facility, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Sheng Ran
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
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26
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Squire OP, Hodgson SA, Chen J, Fedoseev V, de Podesta CK, Weinberger TI, Alireza PL, Grosche FM. Superconductivity beyond the Conventional Pauli Limit in High-Pressure CeSb_{2}. PHYSICAL REVIEW LETTERS 2023; 131:026001. [PMID: 37505955 DOI: 10.1103/physrevlett.131.026001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 05/01/2023] [Accepted: 05/31/2023] [Indexed: 07/30/2023]
Abstract
We report the discovery of superconductivity at a pressure-induced magnetic quantum phase transition in the Kondo lattice system CeSb_{2}, sustained up to magnetic fields that exceed the conventional Pauli limit eightfold. Like CeRh_{2}As_{2}, CeSb_{2} is locally noncentrosymmetric around the Ce site, but the evolution of critical fields and normal state properties as CeSb_{2} is tuned through the quantum phase transition motivates a fundamentally different explanation for its resilience to applied field.
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Affiliation(s)
- Oliver P Squire
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Stephen A Hodgson
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Jiasheng Chen
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Vitaly Fedoseev
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | | | | | - Patricia L Alireza
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - F Malte Grosche
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
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27
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Moore RG, Lu Q, Jeon H, Yao X, Smith T, Pai YY, Chilcote M, Miao H, Okamoto S, Li AP, Oh S, Brahlek M. Monolayer Superconductivity and Tunable Topological Electronic Structure at the Fe(Te,Se)/Bi 2 Te 3 Interface. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2210940. [PMID: 36921318 DOI: 10.1002/adma.202210940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 03/07/2023] [Indexed: 06/02/2023]
Abstract
The interface between 2D topological Dirac states and an s-wave superconductor is expected to support Majorana-bound states (MBS) that can be used for quantum computing applications. Realizing these novel states of matter and their applications requires control over superconductivity and spin-orbit coupling to achieve spin-momentum-locked topological interface states (TIS) which are simultaneously superconducting. While signatures of MBS have been observed in the magnetic vortex cores of bulk FeTe0.55 Se0.45 , inhomogeneity and disorder from doping make these signatures unclear and inconsistent between vortices. Here superconductivity is reported in monolayer (ML) FeTe1-y Sey (Fe(Te,Se)) grown on Bi2 Te3 by molecular beam epitaxy (MBE). Spin and angle-resolved photoemission spectroscopy (SARPES) directly resolve the interfacial spin and electronic structure of Fe(Te,Se)/Bi2 Te3 heterostructures. For y = 0.25, the Fe(Te,Se) electronic structure is found to overlap with the Bi2 Te3 TIS and the desired spin-momentum locking is not observed. In contrast, for y = 0.1, reduced inhomogeneity measured by scanning tunneling microscopy (STM) and a smaller Fe(Te,Se) Fermi surface with clear spin-momentum locking in the topological states are found. Hence, it is demonstrated that the Fe(Te,Se)/Bi2 Te3 system is a highly tunable platform for realizing MBS where reduced doping can improve characteristics important for Majorana interrogation and potential applications.
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Affiliation(s)
- Robert G Moore
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Qiangsheng Lu
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Hoyeon Jeon
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Xiong Yao
- Department of Physics and Astronomy, Rutgers the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Tyler Smith
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Yun-Yi Pai
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Michael Chilcote
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Hu Miao
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Satoshi Okamoto
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - An-Ping Li
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Seongshik Oh
- Department of Physics and Astronomy, Rutgers the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Matthew Brahlek
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
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28
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Gu Q, Carroll JP, Wang S, Ran S, Broyles C, Siddiquee H, Butch NP, Saha SR, Paglione J, Davis JCS, Liu X. Detection of a pair density wave state in UTe 2. Nature 2023; 618:921-927. [PMID: 37380691 DOI: 10.1038/s41586-023-05919-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 03/03/2023] [Indexed: 06/30/2023]
Abstract
Spin-triplet topological superconductors should exhibit many unprecedented electronic properties, including fractionalized electronic states relevant to quantum information processing. Although UTe2 may embody such bulk topological superconductivity1-11, its superconductive order parameter Δ(k) remains unknown12. Many diverse forms for Δ(k) are physically possible12 in such heavy fermion materials13. Moreover, intertwined14,15 density waves of spin (SDW), charge (CDW) and pair (PDW) may interpose, with the latter exhibiting spatially modulating14,15 superconductive order parameter Δ(r), electron-pair density16-19 and pairing energy gap17,20-23. Hence, the newly discovered CDW state24 in UTe2 motivates the prospect that a PDW state may exist in this material24,25. To search for it, we visualize the pairing energy gap with μeV-scale energy resolution using superconductive scanning tunnelling microscopy (STM) tips26-31. We detect three PDWs, each with peak-to-peak gap modulations of around 10 μeV and at incommensurate wavevectors Pi=1,2,3 that are indistinguishable from the wavevectors Qi=1,2,3 of the prevenient24 CDW. Concurrent visualization of the UTe2 superconductive PDWs and the non-superconductive CDWs shows that every Pi:Qi pair exhibits a relative spatial phase δϕ ≈ π. From these observations, and given UTe2 as a spin-triplet superconductor12, this PDW state should be a spin-triplet PDW24,25. Although such states do exist32 in superfluid 3He, for superconductors, they are unprecedented.
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Affiliation(s)
- Qiangqiang Gu
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA
| | - Joseph P Carroll
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA
- Department of Physics, University College Cork, Cork, Ireland
| | - Shuqiu Wang
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA.
- Clarendon Laboratory, University of Oxford, Oxford, UK.
| | - Sheng Ran
- Department of Physics, Washington University in St. Louis, St. Louis, MO, USA
| | - Christopher Broyles
- Department of Physics, Washington University in St. Louis, St. Louis, MO, USA
| | - Hasan Siddiquee
- Department of Physics, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicholas P Butch
- Maryland Quantum Materials Center, University of Maryland, College Park, MD, USA
- NIST Center for Neutron Research, Gaithersburg, MD, USA
| | - Shanta R Saha
- Maryland Quantum Materials Center, University of Maryland, College Park, MD, USA
| | - Johnpierre Paglione
- Maryland Quantum Materials Center, University of Maryland, College Park, MD, USA
- Canadian Institute for Advanced Research, Toronto, Ontario, Canada
| | - J C Séamus Davis
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA.
- Department of Physics, University College Cork, Cork, Ireland.
- Clarendon Laboratory, University of Oxford, Oxford, UK.
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.
| | - Xiaolong Liu
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA.
- Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN, USA.
- Stavropoulos Center for Complex Quantum Matter, University of Notre Dame, Notre Dame, IN, USA.
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29
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Aishwarya A, May-Mann J, Raghavan A, Nie L, Romanelli M, Ran S, Saha SR, Paglione J, Butch NP, Fradkin E, Madhavan V. Magnetic-field-sensitive charge density waves in the superconductor UTe 2. Nature 2023; 618:928-933. [PMID: 37380690 DOI: 10.1038/s41586-023-06005-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 03/23/2023] [Indexed: 06/30/2023]
Abstract
The intense interest in triplet superconductivity partly stems from theoretical predictions of exotic excitations such as non-Abelian Majorana modes, chiral supercurrents and half-quantum vortices1-4. However, fundamentally new and unexpected states may emerge when triplet superconductivity appears in a strongly correlated system. Here we use scanning tunnelling microscopy to reveal an unusual charge-density-wave (CDW) order in the heavy-fermion triplet superconductor UTe2 (refs. 5-8). Our high-resolution maps reveal a multi-component incommensurate CDW whose intensity gets weaker with increasing field, with the CDW eventually disappearing at the superconducting critical field Hc2. To understand the phenomenology of this unusual CDW, we construct a Ginzburg-Landau theory for a uniform triplet superconductor coexisting with three triplet pair-density-wave states. This theory gives rise to daughter CDWs that would be sensitive to magnetic field owing to their origin in a pair-density-wave state and provides a possible explanation for our data. Our discovery of a CDW state that is sensitive to magnetic fields and strongly intertwined with superconductivity provides important information for understanding the order parameters of UTe2.
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Affiliation(s)
- Anuva Aishwarya
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Julian May-Mann
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Institute for Condensed Matter Theory, University of Illinois, Urbana, IL, USA
| | - Arjun Raghavan
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Laimei Nie
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Institute for Condensed Matter Theory, University of Illinois, Urbana, IL, USA
| | - Marisa Romanelli
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Sheng Ran
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Department of Physics, Washington University in St. Louis, St Louis, MO, USA
| | - Shanta R Saha
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Johnpierre Paglione
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
- Canadian Institute for Advanced Research, Toronto, Ontario, Canada
| | - Nicholas P Butch
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Eduardo Fradkin
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Institute for Condensed Matter Theory, University of Illinois, Urbana, IL, USA
| | - Vidya Madhavan
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
- Canadian Institute for Advanced Research, Toronto, Ontario, Canada.
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30
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Guo Y, Qiu D, Shao M, Song J, Wang Y, Xu M, Yang C, Li P, Liu H, Xiong J. Modulations in Superconductors: Probes of Underlying Physics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209457. [PMID: 36504310 DOI: 10.1002/adma.202209457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/16/2022] [Indexed: 06/02/2023]
Abstract
The importance of modulations is elevated to an unprecedented level, due to the delicate conditions required to bring out exotic phenomena in quantum materials, such as topological materials, magnetic materials, and superconductors. Recently, state-of-the-art modulation techniques in material science, such as electric-double-layer transistor, piezoelectric-based strain apparatus, angle twisting, and nanofabrication, have been utilized in superconductors. They not only efficiently increase the tuning capability to the broader ranges but also extend the tuning dimensionality to unprecedented degrees of freedom, including quantum fluctuations of competing phases, electronic correlation, and phase coherence essential to global superconductivity. Here, for a comprehensive review, these techniques together with the established modulation methods, such as elemental substitution, annealing, and polarization-induced gating, are contextualized. Depending on the mechanism of each method, the modulations are categorized into stoichiometric manipulation, electrostatic gating, mechanical modulation, and geometrical design. Their recent advances are highlighted by applications in newly discovered superconductors, e.g., nickelates, Kagome metals, and magic-angle graphene. Overall, the review is to provide systematic modulations in emergent superconductors and serve as the coordinate for future investigations, which can stimulate researchers in superconductivity and other fields to perform various modulations toward a thorough understanding of quantum materials.
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Affiliation(s)
- Yehao Guo
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Dong Qiu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Mingxin Shao
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Jingyan Song
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Yang Wang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Minyi Xu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Chao Yang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Peng Li
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Haiwen Liu
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Jie Xiong
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
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31
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Wan P, Zheliuk O, Yuan NFQ, Peng X, Zhang L, Liang M, Zeitler U, Wiedmann S, Hussey NE, Palstra TTM, Ye J. Orbital Fulde-Ferrell-Larkin-Ovchinnikov state in an Ising superconductor. Nature 2023:10.1038/s41586-023-05967-z. [PMID: 37225992 DOI: 10.1038/s41586-023-05967-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 03/17/2023] [Indexed: 05/26/2023]
Abstract
In superconductors possessing both time and inversion symmetries, the Zeeman effect of an external magnetic field can break the time-reversal symmetry, forming a conventional Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state characterized by Cooper pairings with finite momentum1,2. In superconductors lacking (local) inversion symmetry, the Zeeman effect may still act as the underlying mechanism of FFLO states by interacting with spin-orbit coupling (SOC). Specifically, the interplay between the Zeeman effect and Rashba SOC can lead to the formation of more accessible Rashba FFLO states that cover broader regions in the phase diagram3-5. However, when the Zeeman effect is suppressed because of spin locking in the presence of Ising-type SOC, the conventional FFLO scenarios are no longer effective. Instead, an unconventional FFLO state is formed by coupling the orbital effect of magnetic fields with SOC, providing an alternative mechanism in superconductors with broken inversion symmetries6-8. Here we report the discovery of such an orbital FFLO state in the multilayer Ising superconductor 2H-NbSe2. Transport measurements show that the translational and rotational symmetries are broken in the orbital FFLO state, providing the hallmark signatures of finite-momentum Cooper pairings. We establish the entire orbital FFLO phase diagram, consisting of a normal metal, a uniform Ising superconducting phase and a six-fold orbital FFLO state. This study highlights an alternative route to achieving finite-momentum superconductivity and provides a universal mechanism to preparing orbital FFLO states in similar materials with broken inversion symmetries.
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Affiliation(s)
- Puhua Wan
- Device Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
| | - Oleksandr Zheliuk
- Device Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - Noah F Q Yuan
- School of Science, Harbin Institute of Technology, Shenzhen, China
| | - Xiaoli Peng
- Device Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
| | - Le Zhang
- Device Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
| | - Minpeng Liang
- Device Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
| | - Uli Zeitler
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - Steffen Wiedmann
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - Nigel E Hussey
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
- H. H. Wills Physics Laboratory, University of Bristol, Bristol, UK
| | - Thomas T M Palstra
- Nano Electronic Materials, University of Twente, Enschede, The Netherlands
| | - Jianting Ye
- Device Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
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32
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Ishihara K, Roppongi M, Kobayashi M, Imamura K, Mizukami Y, Sakai H, Opletal P, Tokiwa Y, Haga Y, Hashimoto K, Shibauchi T. Chiral superconductivity in UTe 2 probed by anisotropic low-energy excitations. Nat Commun 2023; 14:2966. [PMID: 37221184 DOI: 10.1038/s41467-023-38688-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 05/08/2023] [Indexed: 05/25/2023] Open
Abstract
Chiral spin-triplet superconductivity is a topologically nontrivial pairing state with broken time-reversal symmetry, which can host Majorana quasiparticles. The heavy-fermion superconductor UTe2 exhibits peculiar properties of spin-triplet pairing, and the possible chiral state has been actively discussed. However, the symmetry and nodal structure of its order parameter in the bulk, which determine the Majorana surface states, remains controversial. Here we focus on the number and positions of superconducting gap nodes in the ground state of UTe2. Our magnetic penetration depth measurements for three field orientations in three crystals all show the power-law temperature dependence with exponents close to 2, which excludes single-component spin-triplet states. The anisotropy of low-energy quasiparticle excitations indicates multiple point nodes near the ky- and kz-axes in momentum space. These results can be consistently explained by a chiral B3u + iAu non-unitary state, providing fundamentals of the topological properties in UTe2.
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Affiliation(s)
- Kota Ishihara
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan.
| | - Masaki Roppongi
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan
| | - Masayuki Kobayashi
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan
| | - Kumpei Imamura
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan
| | - Yuta Mizukami
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan
- Department of Physics, Graduate School of Science, Tohoku University, 6-3, Aramaki Aza-Aoba, Aoba-ku, Sendai, 980-8578, Japan
| | - Hironori Sakai
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - Petr Opletal
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - Yoshifumi Tokiwa
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - Yoshinori Haga
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - Kenichiro Hashimoto
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan
| | - Takasada Shibauchi
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba, 277-8561, Japan.
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33
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Sakai H, Tokiwa Y, Opletal P, Kimata M, Awaji S, Sasaki T, Aoki D, Kambe S, Tokunaga Y, Haga Y. Field Induced Multiple Superconducting Phases in UTe_{2} along Hard Magnetic Axis. PHYSICAL REVIEW LETTERS 2023; 130:196002. [PMID: 37243663 DOI: 10.1103/physrevlett.130.196002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/19/2022] [Accepted: 04/04/2023] [Indexed: 05/29/2023]
Abstract
The superconducting (SC) phase diagram in uranium ditelluride is explored under magnetic fields (H) along the hard magnetic b axis using a high-quality single crystal with T_{c}=2.1 K. Simultaneous electrical resistivity and ac magnetic susceptibility measurements discern low- and high-field SC (LFSC and HFSC, respectively) phases with contrasting field-angular dependence. Crystal quality increases the upper critical field of the LFSC phase, but the H^{*} of ∼15 T, at which the HFSC phase appears, is always the same through the various crystals. A phase boundary signature is also observed inside the LFSC phase near H^{*}, indicating an intermediate SC phase characterized by small flux pinning forces.
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Affiliation(s)
- H Sakai
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Y Tokiwa
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - P Opletal
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - M Kimata
- Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japan
| | - S Awaji
- High Field Laboratory for Superconducting Materials, Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - T Sasaki
- Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japan
| | - D Aoki
- Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
| | - S Kambe
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Y Tokunaga
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Y Haga
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
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34
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Iguchi Y, Man H, Thomas SM, Ronning F, Rosa PFS, Moler KA. Microscopic Imaging Homogeneous and Single Phase Superfluid Density in UTe_{2}. PHYSICAL REVIEW LETTERS 2023; 130:196003. [PMID: 37243629 DOI: 10.1103/physrevlett.130.196003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/21/2022] [Accepted: 04/04/2023] [Indexed: 05/29/2023]
Abstract
Odd-parity superconductor UTe_{2} shows spontaneous time-reversal symmetry breaking and multiple superconducting phases, which imply chiral superconductivity, but only in a subset of samples. Here we microscopically observe a homogeneous superfluid density n_{s} on the surface of UTe_{2} and an enhanced superconducting transition temperature near the edges. We also detect vortex-antivortex pairs even at zero magnetic field, indicating the existence of a hidden internal field. The temperature dependence of n_{s}, determined independent of sample geometry, does not support point nodes along the b axis for a quasi-2D Fermi surface and provides no evidence for multiple phase transitions in UTe_{2}.
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Affiliation(s)
- Yusuke Iguchi
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Huiyuan Man
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
- Stanford Nano Shared Facilities, Stanford University, Stanford, California 94305, USA
| | - S M Thomas
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Filip Ronning
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | | | - Kathryn A Moler
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
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35
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Ikeda A, Matsuda YH, Sato K, Ishii Y, Sawabe H, Nakamura D, Takeyama S, Nasu J. Signature of spin-triplet exciton condensations in LaCoO 3 at ultrahigh magnetic fields up to 600 T. Nat Commun 2023; 14:1744. [PMID: 37015917 PMCID: PMC10073196 DOI: 10.1038/s41467-023-37125-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 02/28/2023] [Indexed: 04/06/2023] Open
Abstract
Bose-Einstein condensation of electron-hole pairs, exciton condensation, has been effortfully investigated since predicted 60 years ago. Irrefutable evidence has still been lacking due to experimental difficulties in verifying the condensation of the charge neutral and non-magnetic spin-singlet excitons. Whilst, condensation of spin-triplet excitons is a promising frontier because spin supercurrent and spin-Seebeck effects will be observable. A canonical cobaltite LaCoO3 under very high magnetic fields is a propitious candidate, yet to be verified. Here, we unveil the exotic phase diagram of LaCoO3 up to 600 T generated using the electromagnetic flux compression method and the state-of-the-art magnetostriction gauge. We found the continuous magnetostriction curves and a bending structure, which suggest the emergence of two distinct spin-triplet exciton condensates. By constructing a phenomenological model, we showed that quantum fluctuations of excitons are crucial for the field-induced successive transitions. The spin-triplet exciton condensation in a cobaltite, which is three-dimensional and thermally equilibrated, opens up a novel venue for spintronics technologies with spin-supercurrent such as a spin Josephson junction.
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Affiliation(s)
- Akihiko Ikeda
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo, 182-8585, Japan.
| | - Yasuhiro H Matsuda
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Keisuke Sato
- National Institute of Technology, Ibaraki College, Hitachinaka, Ibaraki, 312-0011, Japan
| | - Yuto Ishii
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Hironobu Sawabe
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Daisuke Nakamura
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
| | - Shojiro Takeyama
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Joji Nasu
- Department of Physics, Tohoku University, Sendai, Miyagi, 980-8578, Japan
- PRESTO, Japan Science and Technology Agency, Honcho Kawaguchi, Saitama, 332-0012, Japan
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36
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Hazra T, Coleman P. Triplet Pairing Mechanisms from Hund's-Kondo Models: Applications to UTe_{2} and CeRh_{2}As_{2}. PHYSICAL REVIEW LETTERS 2023; 130:136002. [PMID: 37067314 DOI: 10.1103/physrevlett.130.136002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/29/2022] [Accepted: 02/28/2023] [Indexed: 06/19/2023]
Abstract
Observing that several U and Ce based candidate triplet superconductors share a common structural motif, with pairs of magnetic atoms separated by an inversion center, we hypothesize a triplet pairing mechanism based on an interplay of Hund's and Kondo interactions that is unique to this structure. In the presence of Hund's interactions, valence fluctuations generate a triplet superexchange between electrons and local moments. The offset from the center of symmetry allows spin-triplet pairs formed by the resulting Kondo effect to delocalize onto the Fermi surface, precipitating superconductivity. We demonstrate this mechanism within a minimal two-channel Kondo lattice model and present support for this pairing mechanism from existing experiments.
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Affiliation(s)
- Tamaghna Hazra
- Center for Materials Theory, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Piers Coleman
- Center for Materials Theory, Rutgers University, Piscataway, New Jersey 08854, USA
- Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom
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37
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Hu G, Wang C, Wang S, Zhang Y, Feng Y, Wang Z, Niu Q, Zhang Z, Xiang B. Long-range skin Josephson supercurrent across a van der Waals ferromagnet. Nat Commun 2023; 14:1779. [PMID: 36997575 PMCID: PMC10063542 DOI: 10.1038/s41467-023-37603-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 03/23/2023] [Indexed: 04/01/2023] Open
Abstract
AbstractThe emerging field of superconducting spintronics promises new quantum device architectures without energy dissipation. When entering a ferromagnet, a supercurrent commonly behaves as a spin singlet that decays rapidly; in contrast, a spin-triplet supercurrent can transport over much longer distances, and is therefore more desirable, but so far has been observed much less frequently. Here, by using the van der Waals ferromagnet Fe3GeTe2 (F) and spin-singlet superconductor NbSe2 (S), we construct lateral Josephson junctions of S/F/S with accurate interface control to realize long-range skin supercurrent. The observed supercurrent across the ferromagnet can extend over 300 nm, and exhibits distinct quantum interference patterns in an external magnetic field. Strikingly, the supercurrent displays pronounced skin characteristics, with its density peaked at the surfaces or edges of the ferromagnet. Our central findings shed new light on the convergence of superconductivity and spintronics based on two-dimensional materials.
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38
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Shick AB, Halevy I, Tchaplianka M, Legut D. Itinerant-localized dichotomy in magnetic anisotropic properties of U-based ferromagnets. Sci Rep 2023; 13:2646. [PMID: 36788267 PMCID: PMC9929282 DOI: 10.1038/s41598-023-29823-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
The electronic structure, spin and orbital magnetic moments, and the magnetic anisotropy energy in selected U-based compounds are investigated making use of the correlated band theory. First, we demonstrate that the LSDA+U approach with exact atomic limit implemented as a combination of the relativistic density functional theory with the Anderson impurity model provides a good quantitative description for UGa[Formula: see text]. Further, the method is applied to UFe[Formula: see text] and UFe[Formula: see text]Si[Formula: see text] ferromagnets. The calculated positive uniaxial magnetic anisotropy together with negative enthalpy of formation for UFe[Formula: see text]Si[Formula: see text] make it as a candidate for the magnetically hard materials. Our studies suggest a viable route for further development of the rare-earth-lean permanent magnets by replacing a part of U atoms by some rare-earth like Sm in UFe[Formula: see text]Si[Formula: see text].
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Affiliation(s)
- Alexander B. Shick
- grid.418095.10000 0001 1015 3316Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 18221 Prague, Czech Republic ,grid.13992.300000 0004 0604 7563Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, 76100 Rehovoth, Israel ,grid.440850.d0000 0000 9643 2828IT4Innovations and Nanotechnology Centre, CEET, VSB-Technical University of Ostrava, 17. listopadu 2172/15, 70800 Ostrava-Poruba, Czech Republic
| | - Itzhak Halevy
- grid.7489.20000 0004 1937 0511Nuclear Engineering Unit, Ben Gurion University of the Negev, 84105 Beer-sheva, Israel
| | - Maxim Tchaplianka
- grid.418095.10000 0001 1015 3316Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 18221 Prague, Czech Republic
| | - Dominik Legut
- grid.440850.d0000 0000 9643 2828IT4Innovations and Nanotechnology Centre, CEET, VSB-Technical University of Ostrava, 17. listopadu 2172/15, 70800 Ostrava-Poruba, Czech Republic
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39
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Topological Structure of the Order Parameter of Unconventional Superconductors Based on d- and f- Elements. Symmetry (Basel) 2023. [DOI: 10.3390/sym15020376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The superconducting order parameter (SOP) of a triplet superconductor UTe2 was constructed using the topological space group approach, in which, in contrast to phenomenological and topological approaches, the single pair function and phase winding in condensate are different quantities. The connection between them is investigated for the D2h point group and the m′m′m magnetic group. It is shown how a non-unitary pair function of UTe2 can be constructed using one-dimensional real irreducible representations and Ginzburg–Landau phase winding. It is also shown that the total phase winding is non-zero in magnetic symmetry only. Experimental data on the superconducting order parameter of topological superconductors UPt3, Sr2RuO4, LaPt3P, and UTe2 are considered and peculiarities of their nodal structures are connected with the theoretical results of the topological space group approach.
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40
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Yang YF. An emerging global picture of heavy fermion physics. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 35:103002. [PMID: 36542859 DOI: 10.1088/1361-648x/acadc4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
Recent progresses using state-of-the-art experimental techniques have motivated a number of new insights on heavy fermion physics. This article gives a brief summary of the author's research along this direction. We discuss five major topics including: (1) development of phase coherence and two-stage hybridization; (2) two-fluid behavior and hidden universal scaling; (3) quantum phase transitions and fractionalized heavy fermion liquid; (4) quantum critical superconductivity; (5) material-specific properties. These cover the most essential parts of heavy fermion physics and lead to an emerging global picture beyond conventional theories based on mean-field or local approximations.
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Affiliation(s)
- Yi-Feng Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
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41
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Lapierre B, Neupert T, Trifunovic L. Topologically Localized Insulators. PHYSICAL REVIEW LETTERS 2022; 129:256401. [PMID: 36608229 DOI: 10.1103/physrevlett.129.256401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 06/30/2022] [Accepted: 11/07/2022] [Indexed: 06/17/2023]
Abstract
We show that fully localized, three-dimensional, time-reversal-symmetry-broken insulators do not belong to a single phase of matter but can realize topologically distinct phases that are labeled by integers. The phase transition occurs only when the system becomes conducting at some filling. We find that these novel topological phases are fundamentally distinct from insulators without disorder: they are guaranteed to host delocalized boundary states giving rise to the quantized boundary Hall conductance, whose value is equal to the bulk topological invariant.
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Affiliation(s)
- Bastien Lapierre
- Department of Physics, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Titus Neupert
- Department of Physics, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Luka Trifunovic
- Department of Physics, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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42
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Poniatowski NR, Curtis JB, Bøttcher CGL, Galitski VM, Yacoby A, Narang P, Demler E. Surface Cooper-Pair Spin Waves in Triplet Superconductors. PHYSICAL REVIEW LETTERS 2022; 129:237002. [PMID: 36563226 DOI: 10.1103/physrevlett.129.237002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 08/08/2022] [Accepted: 11/10/2022] [Indexed: 06/17/2023]
Abstract
We study the electrodynamics of spin triplet superconductors including dipolar interactions, which give rise to an interplay between the collective spin dynamics of the condensate and orbital Meissner screening currents. Within this theory, we identify a class of spin waves that originate from the coupled dynamics of the spin-symmetry breaking triplet order parameter and the electromagnetic field. In particular, we study magnetostatic spin wave modes that are localized to the sample surface. We show that these surface modes can be excited and detected using experimental techniques such as microwave spin wave resonance spectroscopy or nitrogen-vacancy magnetometry, and propose that the detection of these modes offers a means for the identification of spin triplet superconductivity.
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Affiliation(s)
| | - Jonathan B Curtis
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- John A. Paulson School of Applied Sciences and Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
| | | | - Victor M Galitski
- Joint Quantum Institute, Department of Physics, University of Maryland, College Park, Maryland 20742, USA
| | - Amir Yacoby
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- John A. Paulson School of Applied Sciences and Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Prineha Narang
- John A. Paulson School of Applied Sciences and Engineering, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Eugene Demler
- Institute for Theoretical Physics, ETH Zürich, 8093 Zürich, Switzerland
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43
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Singlet and triplet Cooper pair splitting in hybrid superconducting nanowires. Nature 2022; 612:448-453. [PMID: 36418399 DOI: 10.1038/s41586-022-05352-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/15/2022] [Indexed: 11/25/2022]
Abstract
In most naturally occurring superconductors, electrons with opposite spins form Cooper pairs. This includes both conventional s-wave superconductors such as aluminium, as well as high-transition-temperature, d-wave superconductors. Materials with intrinsic p-wave superconductivity, hosting Cooper pairs made of equal-spin electrons, have not been conclusively identified, nor synthesized, despite promising progress1-3. Instead, engineered platforms where s-wave superconductors are brought into contact with magnetic materials have shown convincing signatures of equal-spin pairing4-6. Here we directly measure equal-spin pairing between spin-polarized quantum dots. This pairing is proximity-induced from an s-wave superconductor into a semiconducting nanowire with strong spin-orbit interaction. We demonstrate such pairing by showing that breaking a Cooper pair can result in two electrons with equal spin polarization. Our results demonstrate controllable detection of singlet and triplet pairing between the quantum dots. Achieving such triplet pairing in a sequence of quantum dots will be required for realizing an artificial Kitaev chain7-9.
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44
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Vallejo KD, Kabir F, Poudel N, Marianetti CA, Hurley DH, Simmonds PJ, Dennett CA, Gofryk K. Advances in actinide thin films: synthesis, properties, and future directions. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 85:123101. [PMID: 36179676 DOI: 10.1088/1361-6633/ac968e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Actinide-based compounds exhibit unique physics due to the presence of 5f electrons, and serve in many cases as important technological materials. Targeted thin film synthesis of actinide materials has been successful in generating high-purity specimens in which to study individual physical phenomena. These films have enabled the study of the unique electron configuration, strong mass renormalization, and nuclear decay in actinide metals and compounds. The growth of these films, as well as their thermophysical, magnetic, and topological properties, have been studied in a range of chemistries, albeit far fewer than most classes of thin film systems. This relative scarcity is the result of limited source material availability and safety constraints associated with the handling of radioactive materials. Here, we review recent work on the synthesis and characterization of actinide-based thin films in detail, describing both synthesis methods and modeling techniques for these materials. We review reports on pyrometallurgical, solution-based, and vapor deposition methods. We highlight the current state-of-the-art in order to construct a path forward to higher quality actinide thin films and heterostructure devices.
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Affiliation(s)
- Kevin D Vallejo
- Condensed Matter and Materials Physics, Idaho National Laboratory, Idaho Falls, ID 83415,United States of America
| | - Firoza Kabir
- Condensed Matter and Materials Physics, Idaho National Laboratory, Idaho Falls, ID 83415,United States of America
- Glenn T Seaborg Institute, Idaho National Laboratory, Idaho Falls, ID 83415, United States of America
| | - Narayan Poudel
- Condensed Matter and Materials Physics, Idaho National Laboratory, Idaho Falls, ID 83415,United States of America
| | - Chris A Marianetti
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, United States of America
| | - David H Hurley
- Condensed Matter and Materials Physics, Idaho National Laboratory, Idaho Falls, ID 83415,United States of America
| | - Paul J Simmonds
- Department of Physics, Boise State University, Boise, ID 83725, United States of America
- Micron School of Materials Science and Engineering, Boise State University, Boise, ID 83725,United States of America
| | - Cody A Dennett
- Condensed Matter and Materials Physics, Idaho National Laboratory, Idaho Falls, ID 83415,United States of America
| | - Krzysztof Gofryk
- Condensed Matter and Materials Physics, Idaho National Laboratory, Idaho Falls, ID 83415,United States of America
- Glenn T Seaborg Institute, Idaho National Laboratory, Idaho Falls, ID 83415, United States of America
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45
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Li Y, Zhang S, Chen F, Wei L, Zhang Z, Xiao H, Gao H, Chen M, Liang S, Pei D, Xu L, Watanabe K, Taniguchi T, Yang L, Miao F, Liu J, Cheng B, Wang M, Chen Y, Liu Z. Observation of Coexisting Dirac Bands and Moiré Flat Bands in Magic-Angle Twisted Trilayer Graphene. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2205996. [PMID: 36043946 DOI: 10.1002/adma.202205996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/10/2022] [Indexed: 06/15/2023]
Abstract
Moiré superlattices that consist of two or more layers of 2D materials stacked together with a small twist angle have emerged as a tunable platform to realize various correlated and topological phases, such as Mott insulators, unconventional superconductivity, and quantum anomalous Hall effect. Recently, magic-angle twisted trilayer graphene (MATTG) has shown both robust superconductivity similar to magic-angle twisted bilayer graphene and other unique properties, including the Pauli-limit violating and re-entrant superconductivity. These rich properties are deeply rooted in its electronic structure under the influence of distinct moiré potential and mirror symmetry. Here, combining nanometer-scale spatially resolved angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy, the as-yet unexplored band structure of MATTG near charge neutrality is systematically measured. These measurements reveal the coexistence of the distinct dispersive Dirac band with the emergent moiré flat band, showing nice agreement with the theoretical calculations. These results serve as a stepstone for further understanding of the unconventional superconductivity in MATTG.
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Affiliation(s)
- Yiwei Li
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- Institute for Advanced Studies, Wuhan University, Luojiashan Street, Wuhan, Hubei, 430072, P. R. China
| | - Shihao Zhang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 200031, P. R. China
| | - Fanqiang Chen
- National Laboratory of Solid State Microstructures, School of Physics, Institute of Brain-Inspired Intelligence, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China
| | - Liyang Wei
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
| | - Zonglin Zhang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
| | - Hanbo Xiao
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
| | - Han Gao
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
| | - Moyu Chen
- National Laboratory of Solid State Microstructures, School of Physics, Institute of Brain-Inspired Intelligence, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China
| | - Shijun Liang
- National Laboratory of Solid State Microstructures, School of Physics, Institute of Brain-Inspired Intelligence, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China
| | - Ding Pei
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 200031, P. R. China
| | - Lixuan Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, P. R. China
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Lexian Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, P. R. China
- Frontier Science Center for Quantum Information, Beijing, 100084, P. R. China
| | - Feng Miao
- National Laboratory of Solid State Microstructures, School of Physics, Institute of Brain-Inspired Intelligence, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China
| | - Jianpeng Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 200031, P. R. China
| | - Bin Cheng
- Institute of Interdisciplinary Physical Sciences, School of Science, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Meixiao Wang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 200031, P. R. China
| | - Yulin Chen
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 200031, P. R. China
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, P. R. China
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, OX1 3PU, UK
| | - Zhongkai Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 200031, P. R. China
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Lai Y, Chan JY, Baumbach RE. Electronic landscape of the f-electron intermetallics with the ThCr 2Si 2 structure. SCIENCE ADVANCES 2022; 8:eabp8264. [PMID: 35947661 PMCID: PMC9365280 DOI: 10.1126/sciadv.abp8264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Although strongly correlated f-electron systems are well known as reservoirs for quantum phenomena, a persistent challenge is to design specific states. What is often missing are simple ways to determine whether a given compound can be expected to exhibit certain behaviors and what tuning vector(s) would be useful to select the ground state. In this review, we address this question by aggregating information about Ce, Eu, Yb, and U compounds with the ThCr2Si2 structure. We construct electronic/magnetic state maps that are parameterized in terms of unit cell volumes and d-shell filling, which reveals useful trends including that (i) the magnetic and nonmagnetic examples are well separated, and (ii) the crossover regions harbor the examples with exotic states. These insights are used to propose structural/chemical regions of interest in these and related materials, with the goal of accelerating discovery of the next generation of f-electron quantum materials.
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Affiliation(s)
- You Lai
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA
| | | | - Ryan E. Baumbach
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA
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47
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Tang F, Ono S, Wan X, Watanabe H. High-Throughput Investigations of Topological and Nodal Superconductors. PHYSICAL REVIEW LETTERS 2022; 129:027001. [PMID: 35867454 DOI: 10.1103/physrevlett.129.027001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/01/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
The theory of symmetry indicators has enabled database searches for topological materials in normal conducting phases, which has led to several encyclopedic topological material databases. To date, such a database for topological superconductors is yet to be achieved because of the lack of information about pairing symmetries of realistic materials. In this Letter, sidestepping this issue, we tackle an alternative problem: the predictions of topological and nodal superconductivity in materials for each single-valued representation of point groups. Based on recently developed symmetry indicators for superconductors, we provide comprehensive mappings from pairing symmetries to the topological or nodal superconducting nature for nonmagnetic materials listed in the Inorganic Crystal Structure Database. We quantitatively show that around 90% of computed materials are topological or nodal superconductors when a pairing that belongs to a one-dimensional nontrivial representation of point groups is assumed. When materials are representation-enforced nodal superconductors, positions and shapes of the nodes are also identified. When combined with experiments, our results will help us understand the pairing mechanism and facilitate realizations of the long-sought Majorana fermions promising for topological quantum computations.
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Affiliation(s)
- Feng Tang
- National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, China and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Seishiro Ono
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
| | - Xiangang Wan
- National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, China and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Haruki Watanabe
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
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48
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Kyrk T, Bravo M, McCandless GT, Lapidus SH, Chan JY. Investigating the A n+1B n X 3n+1 Homologous Series: A New Platform for Studying Magnetic Praseodymium Based Intermetallics. ACS OMEGA 2022; 7:19048-19057. [PMID: 35721977 PMCID: PMC9202054 DOI: 10.1021/acsomega.2c02152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
The recent discovery of the A n+1B n X3n+1 (A = lanthanide, B = transition metal, X = tetrel) homologous series provides a new platform to study the structure-property relationships of highly correlated electron systems. Several members of Ce n+1Co n Ge3n+1 (n = 1, 4, 5, 6, and ∞) show evidence of heavy electron behavior with complex magnetic interactions. While the Ce analogues have been investigated, only n = 1, 2, and ∞ of Pr n+1Co n Ge3n+1 have been synthesized, with n = 1 and 2 showing a nonsinglet magnetic ground state. The Pr analogues can provide a platform for direct comparison of highly correlated behavior. In this perspective, we discuss the impetus for synthesizing the Pr n+1Co n Ge3n+1 members and present the structural characterization of the n = 3 and n = 4 members. We lay the foundation for future investigations of the Pr n+1Co n Ge3n+1 family of compounds and highlight the importance of complementary methods to characterize new quantum materials.
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Affiliation(s)
- Trent
M. Kyrk
- Department
of Chemistry & Biochemistry, Baylor
University, Waco, Texas 76798, United States
| | - Moises Bravo
- Department
of Chemistry & Biochemistry, Baylor
University, Waco, Texas 76798, United States
| | - Gregory T. McCandless
- Department
of Chemistry & Biochemistry, Baylor
University, Waco, Texas 76798, United States
| | - Saul H. Lapidus
- X-ray
Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Julia Y. Chan
- Department
of Chemistry & Biochemistry, Baylor
University, Waco, Texas 76798, United States
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49
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Pressured-induced superconducting phase with large upper critical field and concomitant enhancement of antiferromagnetic transition in EuTe 2. Nat Commun 2022; 13:2975. [PMID: 35624231 PMCID: PMC9142537 DOI: 10.1038/s41467-022-30718-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 05/16/2022] [Indexed: 12/02/2022] Open
Abstract
We report an unusual pressure-induced superconducting state that coexists with an antiferromagnetic ordering of Eu2+ moments and shows a large upper critical field comparable to the Pauli paramagnetic limit in EuTe2. In concomitant with the emergence of superconductivity with Tc ≈ 3–5 K above Pc ≈ 6 GPa, the antiferromagnetic transition temperature TN(P) experiences a quicker rise with the slope increased dramatically from dTN/dP = 0.85(14) K/GPa for P ≤ Pc to 3.7(2) K/GPa for P ≥ Pc. Moreover, the superconducting state can survive in the spin-flop state with a net ferromagnetic component of the Eu2+ sublattice under moderate magnetic fields μ0H ≥ 2 T. Our findings establish the pressurized EuTe2 as a rare magnetic superconductor possessing an intimated interplay between magnetism and superconductivity. Here, the authors report pressure-induced superconductivity with concomitant enhancement of antiferromagnetic transition in layered EuTe2. The superconductivity is distinctly characterized by the high upper critical fields exceeding the Pauli limit among binary tellurides, a prerequisite of the coexistence of ferromagnetism with superconductivity.
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50
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Wolf S, Di Sante D, Schwemmer T, Thomale R, Rachel S. Triplet Superconductivity from Nonlocal Coulomb Repulsion in an Atomic Sn Layer Deposited onto a Si(111) Substrate. PHYSICAL REVIEW LETTERS 2022; 128:167002. [PMID: 35522509 DOI: 10.1103/physrevlett.128.167002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 03/29/2022] [Indexed: 06/14/2023]
Abstract
Atomic layers deposited on semiconductor substrates introduce a platform for the realization of the extended electronic Hubbard model, where the consideration of electronic repulsion beyond the on-site term is paramount. Recently, the onset of superconductivity at 4.7 K has been reported in the hole-doped triangular lattice of tin atoms on a silicon substrate. Through renormalization group methods designed for weak and intermediate coupling, we investigate the nature of the superconducting instability in hole-doped Sn/Si(111). We find that the extended Hubbard nature of interactions is crucial to yield triplet pairing, which is f-wave (p-wave) for moderate (higher) hole doping. In light of persisting challenges to tailor triplet pairing in an electronic material, our finding promises to pave unprecedented ways for engineering unconventional triplet superconductivity.
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Affiliation(s)
- Sebastian Wolf
- School of Physics, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Domenico Di Sante
- Department of Physics and Astronomy, University of Bologna, 40127 Bologna, Italy
- Center for Computational Quantum Physics, Flatiron Institute, New York, New York 10010, USA
| | - Tilman Schwemmer
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland Campus Süd, Würzburg 97074, Germany
| | - Ronny Thomale
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland Campus Süd, Würzburg 97074, Germany
| | - Stephan Rachel
- School of Physics, University of Melbourne, Parkville, Victoria 3010, Australia
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