1
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Švančara P, Smaniotto P, Solidoro L, MacDonald JF, Patrick S, Gregory R, Barenghi CF, Weinfurtner S. Rotating curved spacetime signatures from a giant quantum vortex. Nature 2024; 628:66-70. [PMID: 38509373 PMCID: PMC10990935 DOI: 10.1038/s41586-024-07176-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 02/07/2024] [Indexed: 03/22/2024]
Abstract
Gravity simulators1 are laboratory systems in which small excitations such as sound2 or surface waves3,4 behave as fields propagating on a curved spacetime geometry. The analogy between gravity and fluids requires vanishing viscosity2-4, a feature naturally realized in superfluids such as liquid helium or cold atomic clouds5-8. Such systems have been successful in verifying key predictions of quantum field theory in curved spacetime7-11. In particular, quantum simulations of rotating curved spacetimes indicative of astrophysical black holes require the realization of an extensive vortex flow12 in superfluid systems. Here we demonstrate that, despite the inherent instability of multiply quantized vortices13,14, a stationary giant quantum vortex can be stabilized in superfluid 4He. Its compact core carries thousands of circulation quanta, prevailing over current limitations in other physical systems such as magnons5, atomic clouds6,7 and polaritons15,16. We introduce a minimally invasive way to characterize the vortex flow17,18 by exploiting the interaction of micrometre-scale waves on the superfluid interface with the background velocity field. Intricate wave-vortex interactions, including the detection of bound states and distinctive analogue black hole ringdown signatures, have been observed. These results open new avenues to explore quantum-to-classical vortex transitions and use superfluid helium as a finite-temperature quantum field theory simulator for rotating curved spacetimes19.
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Affiliation(s)
- Patrik Švančara
- School of Mathematical Sciences, University of Nottingham, Nottingham, UK.
- Nottingham Centre of Gravity, University of Nottingham, Nottingham, UK.
| | - Pietro Smaniotto
- School of Mathematical Sciences, University of Nottingham, Nottingham, UK
- Nottingham Centre of Gravity, University of Nottingham, Nottingham, UK
| | - Leonardo Solidoro
- School of Mathematical Sciences, University of Nottingham, Nottingham, UK
- Nottingham Centre of Gravity, University of Nottingham, Nottingham, UK
| | - James F MacDonald
- School of Physics & Astronomy, University of Nottingham, Nottingham, UK
| | - Sam Patrick
- Department of Physics, King's College London, University of London, London, UK
| | - Ruth Gregory
- Department of Physics, King's College London, University of London, London, UK
- Perimeter Institute, Waterloo, Ontario, Canada
| | - Carlo F Barenghi
- School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, UK
| | - Silke Weinfurtner
- School of Mathematical Sciences, University of Nottingham, Nottingham, UK.
- Nottingham Centre of Gravity, University of Nottingham, Nottingham, UK.
- Perimeter Institute, Waterloo, Ontario, Canada.
- Centre for the Mathematics and Theoretical Physics of Quantum Non-Equilibrium Systems (CQNE), University of Nottingham, Nottingham, UK.
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2
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Mitra S, Jiménez-Galán Á, Aulich M, Neuhaus M, Silva REF, Pervak V, Kling MF, Biswas S. Light-wave-controlled Haldane model in monolayer hexagonal boron nitride. Nature 2024; 628:752-757. [PMID: 38622268 PMCID: PMC11041748 DOI: 10.1038/s41586-024-07244-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 02/27/2024] [Indexed: 04/17/2024]
Abstract
In recent years, the stacking and twisting of atom-thin structures with matching crystal symmetry has provided a unique way to create new superlattice structures in which new properties emerge1,2. In parallel, control over the temporal characteristics of strong light fields has allowed researchers to manipulate coherent electron transport in such atom-thin structures on sublaser-cycle timescales3,4. Here we demonstrate a tailored light-wave-driven analogue to twisted layer stacking. Tailoring the spatial symmetry of the light waveform to that of the lattice of a hexagonal boron nitride monolayer and then twisting this waveform result in optical control of time-reversal symmetry breaking5 and the realization of the topological Haldane model6 in a laser-dressed two-dimensional insulating crystal. Further, the parameters of the effective Haldane-type Hamiltonian can be controlled by rotating the light waveform, thus enabling ultrafast switching between band structure configurations and allowing unprecedented control over the magnitude, location and curvature of the bandgap. This results in an asymmetric population between complementary quantum valleys that leads to a measurable valley Hall current7, which can be detected by optical harmonic polarimetry. The universality and robustness of our scheme paves the way to valley-selective bandgap engineering on the fly and unlocks the possibility of creating few-femtosecond switches with quantum degrees of freedom.
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Affiliation(s)
- Sambit Mitra
- Max Planck Institute of Quantum Optics, Garching, Germany
- Physics Department, Ludwig-Maximilian University of Munich, Garching, Germany
| | - Álvaro Jiménez-Galán
- Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain.
- Max Born Institute, Berlin, Germany.
| | - Mario Aulich
- Physics Department, Ludwig-Maximilian University of Munich, Garching, Germany
- SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Marcel Neuhaus
- Max Planck Institute of Quantum Optics, Garching, Germany
- Physics Department, Ludwig-Maximilian University of Munich, Garching, Germany
- SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Rui E F Silva
- Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Volodymyr Pervak
- Max Planck Institute of Quantum Optics, Garching, Germany
- Physics Department, Ludwig-Maximilian University of Munich, Garching, Germany
| | - Matthias F Kling
- Max Planck Institute of Quantum Optics, Garching, Germany
- Physics Department, Ludwig-Maximilian University of Munich, Garching, Germany
- SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Shubhadeep Biswas
- Max Planck Institute of Quantum Optics, Garching, Germany.
- Physics Department, Ludwig-Maximilian University of Munich, Garching, Germany.
- SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
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3
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Nguyen MD, Simon J, Scott JW, Zimmerman AM, Tsai YCC, Halperin WP. Orbital-flop transition of superfluid 3He in anisotropic silica aerogel. Nat Commun 2024; 15:201. [PMID: 38172106 PMCID: PMC10764773 DOI: 10.1038/s41467-023-44557-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 12/12/2023] [Indexed: 01/05/2024] Open
Abstract
Superfluid 3He is a paradigm for odd-parity Cooper pairing, ranging from neutron stars to uranium-based superconducting compounds. Recently it has been shown that 3He, imbibed in anisotropic silica aerogel with either positive or negative strain, preferentially selects either the chiral A-phase or the time-reversal-symmetric B-phase. This control over basic order parameter symmetry provides a useful model for understanding imperfect unconventional superconductors. For both phases, the orbital quantization axis is fixed by the direction of strain. Unexpectedly, at a specific temperature Tx, the orbital axis flops by 90∘, but in reverse order for A and B-phases. Aided by diffusion limited cluster aggregation simulations of anisotropic aerogel and small angle X-ray measurements, we are able to classify these aerogels as either "planar" and "nematic" concluding that the orbital-flop is caused by competition between short and long range structures in these aerogels.
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Affiliation(s)
- M D Nguyen
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA.
| | - Joshua Simon
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA
| | - J W Scott
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA
| | - A M Zimmerman
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA
| | - Y C Cincia Tsai
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA
| | - W P Halperin
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA.
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4
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Boltnev RE, Vasiliev MM, Petrov OF. Two-dimensional Brownian motion of active particle on superfluid helium surface. Sci Rep 2023; 13:22538. [PMID: 38110441 PMCID: PMC10728076 DOI: 10.1038/s41598-023-49672-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 12/11/2023] [Indexed: 12/20/2023] Open
Abstract
We report an experimental study of the 2D dynamics of active particles driven by quantum vortices on the free surface of superfluid helium at T = 1.45 К. The particle motion at short times (< 25 ms) relates to anomalous diffusion mode typical for active particles, while for longer times it corresponds to normal diffusion mode. The values of the rotational and translational kinetic energies of the particle allow to determine for the first time the intensity of the particle-vortex interaction and the dissipation rate of the vortex bundle energy. Strong bonding between a particle and a vortex is explained by coupling of normal and superfluid components.
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Affiliation(s)
- Roman E Boltnev
- Joint Institute for High Temperatures of Russian Academy of Sciences, Izhorskaya Str. 13/2, Moscow, Russia, 125412.
| | - Mikhail M Vasiliev
- Joint Institute for High Temperatures of Russian Academy of Sciences, Izhorskaya Str. 13/2, Moscow, Russia, 125412
| | - Oleg F Petrov
- Joint Institute for High Temperatures of Russian Academy of Sciences, Izhorskaya Str. 13/2, Moscow, Russia, 125412
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5
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Qi R, Joe AY, Zhang Z, Zeng Y, Zheng T, Feng Q, Xie J, Regan E, Lu Z, Taniguchi T, Watanabe K, Tongay S, Crommie MF, MacDonald AH, Wang F. Thermodynamic behavior of correlated electron-hole fluids in van der Waals heterostructures. Nat Commun 2023; 14:8264. [PMID: 38092731 PMCID: PMC10719388 DOI: 10.1038/s41467-023-43799-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 11/20/2023] [Indexed: 12/17/2023] Open
Abstract
Coupled two-dimensional electron-hole bilayers provide a unique platform to study strongly correlated Bose-Fermi mixtures in condensed matter. Electrons and holes in spatially separated layers can bind to form interlayer excitons, composite Bosons expected to support high-temperature exciton condensates. The interlayer excitons can also interact strongly with excess charge carriers when electron and hole densities are unequal. Here, we use optical spectroscopy to quantitatively probe the local thermodynamic properties of strongly correlated electron-hole fluids in MoSe2/hBN/WSe2 heterostructures. We observe a discontinuity in the electron and hole chemical potentials at matched electron and hole densities, a definitive signature of an excitonic insulator ground state. The excitonic insulator is stable up to a Mott density of ~0.8 × 1012 cm-2 and has a thermal ionization temperature of ~70 K. The density dependence of the electron, hole, and exciton chemical potentials reveals strong correlation effects across the phase diagram. Compared with a non-interacting uniform charge distribution, the correlation effects lead to significant attractive exciton-exciton and exciton-charge interactions in the electron-hole fluid. Our work highlights the unique quantum behavior that can emerge in strongly correlated electron-hole systems.
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Affiliation(s)
- Ruishi Qi
- Department of Physics, University of California, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Andrew Y Joe
- Department of Physics, University of California, Berkeley, CA, 94720, USA.
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Zuocheng Zhang
- Department of Physics, University of California, Berkeley, CA, 94720, USA
| | - Yongxin Zeng
- Department of Physics, University of Texas at Austin, Austin, TX, 78712, USA
| | - Tiancheng Zheng
- Department of Physics, University of California, Berkeley, CA, 94720, USA
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Qixin Feng
- Department of Physics, University of California, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Jingxu Xie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Graduate Group in Applied Science and Technology, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Emma Regan
- Department of Physics, University of California, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Graduate Group in Applied Science and Technology, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Zheyu Lu
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Graduate Group in Applied Science and Technology, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Sefaattin Tongay
- School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA
| | - Michael F Crommie
- Department of Physics, University of California, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Allan H MacDonald
- Department of Physics, University of Texas at Austin, Austin, TX, 78712, USA
| | - Feng Wang
- Department of Physics, University of California, Berkeley, CA, 94720, USA.
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
- Kavli Energy NanoSciences Institute, University of California Berkeley and Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
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6
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Ravnik J, Vaskivskyi Y, Vodeb J, Diego M, Venturini R, Gerasimenko Y, Kabanov V, Kranjec A, Mihailovic D. Chiral domain dynamics and transient interferences of mirrored superlattices in nonequilibrium electronic crystals. Sci Rep 2023; 13:19622. [PMID: 37949956 PMCID: PMC10638312 DOI: 10.1038/s41598-023-46659-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023] Open
Abstract
Mirror symmetry plays a major role in determining the properties of matter and is of particular interest in condensed many-body systems undergoing symmetry breaking transitions under non-equilibrium conditions. Typically, in the aftermath of such transitions, one of the two possible broken symmetry states is emergent. However, synthetic systems and those formed under non-equilibrium conditions may exhibit metastable states comprising of both left (L) and right (R) handed symmetry. Here we explore the formation of chiral charge-density wave (CDW) domains after a laser quench in 1T-TaS2 with scanning tunneling microscopy. Typically, we observed transient domains of both chiralities, separated spatially from each other by domain walls with different structure. In addition, we observe transient density of states modulations consistent with interference of L and R-handed charge density waves within the surface monolayer. Theoretical modeling of the intertwined domain structures using a classical charged lattice gas model reproduces the experimental domain wall structures. The superposition (S) state cannot be understood classically within the correlated electron model but is found to be consistent with interferences of L and R-handed charge-density waves within domains, confined by surrounding domain walls, vividly revealing an interference of Fermi electrons with opposite chirality, which is not a result of inter-layer interference, but due to the interaction between electrons within a single layer, confined by domain wall boundaries.
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Affiliation(s)
- J Ravnik
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
- Laboratory for Micro and Nanotechnology, Paul Scherrer Institut (PSI), Forschungsstrasse 111, 5232, Villigen, Switzerland
| | - Ye Vaskivskyi
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
- Faculty for Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000, Ljubljana, Slovenia
| | - J Vodeb
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - M Diego
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - R Venturini
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
- Faculty for Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000, Ljubljana, Slovenia
| | - Ya Gerasimenko
- Center of Excellence on Nanoscience and Nanotechnology-Nanocenter (CENN Nanocenter), Jamova 39, 1000, Ljubljana, Slovenia
| | - V Kabanov
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - A Kranjec
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - D Mihailovic
- Complex Matter Department, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia.
- Center of Excellence on Nanoscience and Nanotechnology-Nanocenter (CENN Nanocenter), Jamova 39, 1000, Ljubljana, Slovenia.
- Faculty for Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000, Ljubljana, Slovenia.
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7
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Arpaia R, Martinelli L, Sala MM, Caprara S, Nag A, Brookes NB, Camisa P, Li Q, Gao Q, Zhou X, Garcia-Fernandez M, Zhou KJ, Schierle E, Bauch T, Peng YY, Di Castro C, Grilli M, Lombardi F, Braicovich L, Ghiringhelli G. Signature of quantum criticality in cuprates by charge density fluctuations. Nat Commun 2023; 14:7198. [PMID: 37938250 PMCID: PMC10632404 DOI: 10.1038/s41467-023-42961-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 10/25/2023] [Indexed: 11/09/2023] Open
Abstract
The universality of the strange metal phase in many quantum materials is often attributed to the presence of a quantum critical point (QCP), a zero-temperature phase transition ruled by quantum fluctuations. In cuprates, where superconductivity hinders direct QCP observation, indirect evidence comes from the identification of fluctuations compatible with the strange metal phase. Here we show that the recently discovered charge density fluctuations (CDF) possess the right properties to be associated to a quantum phase transition. Using resonant x-ray scattering, we studied the CDF in two families of cuprate superconductors across a wide doping range (up to p = 0.22). At p* ≈ 0.19, the putative QCP, the CDF intensity peaks, and the characteristic energy Δ is minimum, marking a wedge-shaped region in the phase diagram indicative of a quantum critical behavior, albeit with anomalies. These findings strengthen the role of charge order in explaining strange metal phenomenology and provide insights into high-temperature superconductivity.
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Affiliation(s)
- Riccardo Arpaia
- Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296, Göteborg, Sweden.
| | - Leonardo Martinelli
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy
| | - Marco Moretti Sala
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy
| | - Sergio Caprara
- Dipartimento di Fisica, Università di Roma "La Sapienza", P.le Aldo Moro 5, I-00185, Roma, Italy
- CNR-ISC, via dei Taurini 19, I-00185, Roma, Italy
| | - Abhishek Nag
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
| | - Nicholas B Brookes
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38000, Grenoble, France
| | - Pietro Camisa
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy
| | - Qizhi Li
- International Center for Quantum Materials, School of Physics, Peking University, CN-100871, Beijing, China
| | - Qiang Gao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, CN-100190, Beijing, China
| | - Xingjiang Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, CN-100190, Beijing, China
| | | | - Ke-Jin Zhou
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
| | - Enrico Schierle
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, D-12489, Berlin, Germany
| | - Thilo Bauch
- Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296, Göteborg, Sweden
| | - Ying Ying Peng
- International Center for Quantum Materials, School of Physics, Peking University, CN-100871, Beijing, China
| | - Carlo Di Castro
- Dipartimento di Fisica, Università di Roma "La Sapienza", P.le Aldo Moro 5, I-00185, Roma, Italy
| | - Marco Grilli
- Dipartimento di Fisica, Università di Roma "La Sapienza", P.le Aldo Moro 5, I-00185, Roma, Italy
- CNR-ISC, via dei Taurini 19, I-00185, Roma, Italy
| | - Floriana Lombardi
- Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296, Göteborg, Sweden
| | - Lucio Braicovich
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38000, Grenoble, France
| | - Giacomo Ghiringhelli
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy.
- CNR-SPIN, Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy.
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8
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Wang WO, Ding JK, Huang EW, Moritz B, Devereaux TP. Quantitative assessment of the universal thermopower in the Hubbard model. Nat Commun 2023; 14:7064. [PMID: 37923746 PMCID: PMC10624669 DOI: 10.1038/s41467-023-42772-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 10/17/2023] [Indexed: 11/06/2023] Open
Abstract
As primarily an electronic observable, the room-temperature thermopower S in cuprates provides possibilities for a quantitative assessment of the Hubbard model. Using determinant quantum Monte Carlo, we demonstrate agreement between Hubbard model calculations and experimentally measured room-temperature S across multiple cuprate families, both qualitatively in terms of the doping dependence and quantitatively in terms of magnitude. We observe an upturn in S with decreasing temperatures, which possesses a slope comparable to that observed experimentally in cuprates. From our calculations, the doping at which S changes sign occurs in close proximity to a vanishing temperature dependence of the chemical potential at fixed density. Our results emphasize the importance of interaction effects in the systematic assessment of the thermopower S in cuprates.
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Affiliation(s)
- Wen O Wang
- Department of Applied Physics, Stanford University, Stanford, CA, 94305, USA.
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA.
| | - Jixun K Ding
- Department of Applied Physics, Stanford University, Stanford, CA, 94305, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Edwin W Huang
- Department of Physics and Institute of Condensed Matter Theory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN, 46556, USA
- Stavropoulos Center for Complex Quantum Matter, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Brian Moritz
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Thomas P Devereaux
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA.
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, 94305, USA.
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9
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Autti S, Haley RP, Jennings A, Pickett GR, Poole M, Schanen R, Soldatov AA, Tsepelin V, Vonka J, Zavjalov VV, Zmeev DE. Transport of bound quasiparticle states in a two-dimensional boundary superfluid. Nat Commun 2023; 14:6819. [PMID: 37919295 PMCID: PMC10622538 DOI: 10.1038/s41467-023-42520-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 10/13/2023] [Indexed: 11/04/2023] Open
Abstract
The B phase of superfluid 3He can be cooled into the pure superfluid regime, where the thermal quasiparticle density is negligible. The bulk superfluid is surrounded by a quantum well at the boundaries of the container, confining a sea of quasiparticles with energies below that of those in the bulk. We can create a non-equilibrium distribution of these states within the quantum well and observe the dynamics of their motion indirectly. Here we show that the induced quasiparticle currents flow diffusively in the two-dimensional system. Combining this with a direct measurement of energy conservation, we conclude that the bulk superfluid 3He is effectively surrounded by an independent two-dimensional superfluid, which is isolated from the bulk superfluid but which readily interacts with mechanical probes. Our work shows that this two-dimensional quantum condensate and the dynamics of the surface bound states are experimentally accessible, opening the possibility of engineering two-dimensional quantum condensates of arbitrary topology.
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Affiliation(s)
- Samuli Autti
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK.
| | - Richard P Haley
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Asher Jennings
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
- RIKEN Center for Quantum Computing, RIKEN, Wako, 351-0198, Japan
| | - George R Pickett
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Malcolm Poole
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Roch Schanen
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Arkady A Soldatov
- P.L. Kapitza Institute for Physical Problems of RAS, 119334, Moscow, Russia
| | - Viktor Tsepelin
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Jakub Vonka
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | | | - Dmitry E Zmeev
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
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10
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Cassella G, d'Ornellas P, Hodson T, Natori WMH, Knolle J. An exact chiral amorphous spin liquid. Nat Commun 2023; 14:6663. [PMID: 37863892 PMCID: PMC10589230 DOI: 10.1038/s41467-023-42105-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 09/26/2023] [Indexed: 10/22/2023] Open
Abstract
Topological insulator phases of non-interacting particles have been generalized from periodic crystals to amorphous lattices, which raises the question whether topologically ordered quantum many-body phases may similarly exist in amorphous systems? Here we construct a soluble chiral amorphous quantum spin liquid by extending the Kitaev honeycomb model to random lattices with fixed coordination number three. The model retains its exact solubility but the presence of plaquettes with an odd number of sides leads to a spontaneous breaking of time reversal symmetry. We unearth a rich phase diagram displaying Abelian as well as a non-Abelian quantum spin liquid phases with a remarkably simple ground state flux pattern. Furthermore, we show that the system undergoes a finite-temperature phase transition to a conducting thermal metal state and discuss possible experimental realisations.
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Affiliation(s)
- G Cassella
- Blackett Laboratory, Imperial College London, London, SW7 2AZ, United Kingdom
| | - P d'Ornellas
- Blackett Laboratory, Imperial College London, London, SW7 2AZ, United Kingdom.
| | - T Hodson
- Blackett Laboratory, Imperial College London, London, SW7 2AZ, United Kingdom
| | - W M H Natori
- Institut Laue-Langevin, BP 156, 41 Avenue des Martyrs, 38042, Grenoble Cedex 9, France
| | - J Knolle
- Blackett Laboratory, Imperial College London, London, SW7 2AZ, United Kingdom.
- Department of Physics TQM, Technische Universität München, James-Franck-Straße 1, D-85748, Garching, Germany.
- Munich Center for Quantum Science and Technology (MCQST), 80799, Munich, Germany.
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11
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Mai P, Zhao J, Feldman BE, Phillips PW. 1/4 is the new 1/2 when topology is intertwined with Mottness. Nat Commun 2023; 14:5999. [PMID: 37752137 PMCID: PMC10522641 DOI: 10.1038/s41467-023-41465-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 09/01/2023] [Indexed: 09/28/2023] Open
Abstract
In non-interacting systems, bands from non-trivial topology emerge strictly at half-filling and exhibit either the quantum anomalous Hall or spin Hall effects. Here we show using determinantal quantum Monte Carlo and an exactly solvable strongly interacting model that these topological states now shift to quarter filling. A topological Mott insulator is the underlying cause. The peak in the spin susceptibility is consistent with a possible ferromagnetic state at T = 0. The onset of such magnetism would convert the quantum spin Hall to a quantum anomalous Hall effect. While such a symmetry-broken phase typically is accompanied by a gap, we find that the interaction strength must exceed a critical value for this to occur. Hence, we predict that topology can obtain in a gapless phase but only in the presence of interactions in dispersive bands. These results explain the recent quarter-filled quantum anomalous Hall effects seen in moiré systems.
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Affiliation(s)
- Peizhi Mai
- Department of Physics and Institute of Condensed Matter Theory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jinchao Zhao
- Department of Physics and Institute of Condensed Matter Theory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Benjamin E Feldman
- Geballe Laboratory of Advanced Materials, Stanford, CA, 94305, USA
- Department of Physics, Stanford University, Stanford, CA, 94305, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Philip W Phillips
- Department of Physics and Institute of Condensed Matter Theory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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12
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Baten RN, Tian Y, Smith EN, Mueller EJ, Parpia JM. Observation of suppressed viscosity in the normal state of 3He due to superfluid fluctuations. Nat Commun 2023; 14:5834. [PMID: 37730714 PMCID: PMC10511454 DOI: 10.1038/s41467-023-41422-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 08/31/2023] [Indexed: 09/22/2023] Open
Abstract
Evidence of fluctuations in transport have long been predicted in 3He. They are expected to contribute only within 100μK of Tc and play a vital role in the theoretical modeling of ordering; they encode details about the Fermi liquid parameters, pairing symmetry, and scattering phase shifts. It is expected that they will be of crucial importance for transport probes of the topologically nontrivial features of superfluid 3He under strong confinement. Here we characterize the temperature and pressure dependence of the fluctuation signature, by monitoring the quality factor of a quartz tuning fork oscillator. We have observed a fluctuation-driven reduction in the viscosity of bulk 3He, finding data collapse consistent with the predicted theoretical behavior.
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Affiliation(s)
- Rakin N Baten
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - Yefan Tian
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - Eric N Smith
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - Erich J Mueller
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - Jeevak M Parpia
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA.
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13
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O'Rourke MJ, Chan GKL. Entanglement in the quantum phases of an unfrustrated Rydberg atom array. Nat Commun 2023; 14:5397. [PMID: 37669950 PMCID: PMC10480489 DOI: 10.1038/s41467-023-41166-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 08/23/2023] [Indexed: 09/07/2023] Open
Abstract
Recent experimental advances have stimulated interest in the use of large, two-dimensional arrays of Rydberg atoms as a platform for quantum information processing and to study exotic many-body quantum states. However, the native long-range interactions between the atoms complicate experimental analysis and precise theoretical understanding of these systems. Here we use new tensor network algorithms capable of including all long-range interactions to study the ground state phase diagram of Rydberg atoms in a geometrically unfrustrated square lattice array. We find a greatly altered phase diagram from earlier numerical and experimental studies, revealed by studying the phases on the bulk lattice and their analogs in experiment-sized finite arrays. We further describe a previously unknown region with a nematic phase stabilized by short-range entanglement and an order from disorder mechanism. Broadly our results yield a conceptual guide for future experiments, while our techniques provide a blueprint for converging numerical studies in other lattices.
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Affiliation(s)
- Matthew J O'Rourke
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Garnet Kin-Lic Chan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
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14
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Husain AA, Huang EW, Mitrano M, Rak MS, Rubeck SI, Guo X, Yang H, Sow C, Maeno Y, Uchoa B, Chiang TC, Batson PE, Phillips PW, Abbamonte P. Pines' demon observed as a 3D acoustic plasmon in Sr 2RuO 4. Nature 2023; 621:66-70. [PMID: 37558882 PMCID: PMC10482684 DOI: 10.1038/s41586-023-06318-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 06/13/2023] [Indexed: 08/11/2023]
Abstract
The characteristic excitation of a metal is its plasmon, which is a quantized collective oscillation of its electron density. In 1956, David Pines predicted that a distinct type of plasmon, dubbed a 'demon', could exist in three-dimensional (3D) metals containing more than one species of charge carrier1. Consisting of out-of-phase movement of electrons in different bands, demons are acoustic, electrically neutral and do not couple to light, so have never been detected in an equilibrium, 3D metal. Nevertheless, demons are believed to be critical for diverse phenomena including phase transitions in mixed-valence semimetals2, optical properties of metal nanoparticles3, soundarons in Weyl semimetals4 and high-temperature superconductivity in, for example, metal hydrides3,5-7. Here, we present evidence for a demon in Sr2RuO4 from momentum-resolved electron energy-loss spectroscopy. Formed of electrons in the β and γ bands, the demon is gapless with critical momentum qc = 0.08 reciprocal lattice units and room-temperature velocity v = (1.065 ± 0.12) × 105 m s-1 that undergoes a 31% renormalization upon cooling to 30 K because of coupling to the particle-hole continuum. The momentum dependence of the intensity of the demon confirms its neutral character. Our study confirms a 67-year old prediction and indicates that demons may be a pervasive feature of multiband metals.
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Affiliation(s)
- Ali A Husain
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, IL, USA.
| | - Edwin W Huang
- Department of Physics and Institute for Condensed Matter Theory, University of Illinois, Urbana, IL, USA
| | - Matteo Mitrano
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - Melinda S Rak
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, IL, USA
| | - Samantha I Rubeck
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, IL, USA
| | - Xuefei Guo
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, IL, USA
| | - Hongbin Yang
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, USA
| | - Chanchal Sow
- Department of Physics, Kyoto University, Kyoto, Japan
- Department of Physics, Indian Institute of Technology, Kanpur, India
| | - Yoshiteru Maeno
- Department of Physics, Kyoto University, Kyoto, Japan
- Toyota Riken - Kyoto Univ. Research Center (TRiKUC), KUIAS, Kyoto University, Kyoto, Japan
| | - Bruno Uchoa
- Department of Physics and Astronomy, University of Oklahoma, Norman, OK, USA
| | - Tai C Chiang
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, IL, USA
| | - Philip E Batson
- Department of Physics, Rutgers University, Piscataway, NJ, USA
| | - Philip W Phillips
- Department of Physics and Institute for Condensed Matter Theory, University of Illinois, Urbana, IL, USA
| | - Peter Abbamonte
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, IL, USA.
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15
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Blinova A, Zamora-Zamora R, Ollikainen T, Kivioja M, Möttönen M, Hall DS. Observation of an Alice ring in a Bose-Einstein condensate. Nat Commun 2023; 14:5100. [PMID: 37644013 PMCID: PMC10465595 DOI: 10.1038/s41467-023-40710-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 08/08/2023] [Indexed: 08/31/2023] Open
Abstract
Monopoles and vortices are fundamental topological excitations that appear in physical systems spanning enormous scales of size and energy, from the vastness of the early universe to tiny laboratory droplets of nematic liquid crystals and ultracold gases. Although the topologies of vortices and monopoles are distinct from one another, under certain circumstances a monopole can spontaneously and continuously deform into a vortex ring with the curious property that monopoles passing through it are converted into anti-monopoles. However, the observation of such Alice rings has remained a major challenge, due to the scarcity of experimentally accessible monopoles in continuous fields. Here, we present experimental evidence of an Alice ring resulting from the decay of a topological monopole defect in a dilute gaseous 87Rb Bose-Einstein condensate. Our results, in agreement with detailed first-principles simulations, provide an unprecedented opportunity to explore the unique features of a composite excitation that combines the topological features of both a monopole and a vortex ring.
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Affiliation(s)
- Alina Blinova
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA.
- Department of Physics, University of Massachusetts Amherst, Amherst, MA, 01003, USA.
| | - Roberto Zamora-Zamora
- QCD Labs, QTF Centre of Excellence and InstituteQ, Department of Applied Physics, Aalto University, P.O. Box 13500, FI-00076, Espoo, Finland
- Quanscient Oy, Tampere, Finland
| | - Tuomas Ollikainen
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA
- QCD Labs, QTF Centre of Excellence and InstituteQ, Department of Applied Physics, Aalto University, P.O. Box 13500, FI-00076, Espoo, Finland
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
| | - Markus Kivioja
- Faculty of Information Technology, University of Jyväskylä, P.O. Box 35, FI-40014, Jyväskylä, Finland
| | - Mikko Möttönen
- QCD Labs, QTF Centre of Excellence and InstituteQ, Department of Applied Physics, Aalto University, P.O. Box 13500, FI-00076, Espoo, Finland
| | - David S Hall
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA
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16
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Tian Y, Lotnyk D, Eyal A, Zhang K, Zhelev N, Abhilash TS, Chavez A, Smith EN, Hindmarsh M, Saunders J, Mueller E, Parpia JM. Supercooling of the A phase of (3)He. Nat Commun 2023; 14:148. [PMID: 36627275 DOI: 10.1038/s41467-022-35532-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 12/07/2022] [Indexed: 01/11/2023] Open
Abstract
Because of the extreme purity, lack of disorder, and complex order parameter, the first-order superfluid 3He A-B transition is the leading model system for first order transitions in the early universe. Here we report on the path dependence of the supercooling of the A phase over a wide range of pressures below 29.3 bar at nearly zero magnetic field. The A phase can be cooled significantly below the thermodynamic A-B transition temperature. While the extent of supercooling is highly reproducible, it depends strongly upon the cooling trajectory: The metastability of the A phase is enhanced by transiting through regions where the A phase is more stable. We provide evidence that some of the additional supercooling is due to the elimination of B phase nucleation precursors formed upon passage through the superfluid transition. A greater understanding of the physics is essential before 3He can be exploited to model transitions in the early universe.
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17
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Karnaukhov IN. Gapped electron liquid state in the symmetric Anderson lattice, Kondo insulator state. Sci Rep 2022; 12:18607. [PMID: 36329108 PMCID: PMC9633611 DOI: 10.1038/s41598-022-23221-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/27/2022] [Indexed: 11/05/2022] Open
Abstract
The Kondo insulator state (KIS) realized in the symmetric Anderson model at half filling is studied in the framework of a mean field approach. It is shown that the state of the Kondo insulator is realized in a lattice with a double cell and a gapped electron liquid behaves like a gapless Majorana spin liquid. The local moments of d-electrons form a static \documentclass[12pt]{minimal}
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\begin{document}$$Z_2$$\end{document}Z2-field in which band electrons move. The gap value in the quasi-particle excitations spectrum decreases with increasing an external magnetic field and closes at its critical value. The behavior of an electron liquid is studied for an arbitrary dimension of the model. The proposed approach leads to the description of KIS without the need to resort to artificial symmetry breaking to alternative understanding of the physical nature of this phase state.
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Affiliation(s)
- Igor N. Karnaukhov
- grid.435300.10000 0004 0482 7152G.V. Kurdyumov Institute for Metal Physics, 36 Vernadsky Boulevard, Kiev, 03142 Ukraine
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18
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Zvyagin SA, Ponomaryov AN, Wosnitza J, Hirai D, Hiroi Z, Gen M, Kohama Y, Matsuo A, Matsuda YH, Kindo K. Dimensional reduction and incommensurate dynamic correlations in the [Formula: see text] triangular-lattice antiferromagnet Ca 3ReO 5Cl 2. Nat Commun 2022; 13:6310. [PMID: 36274086 PMCID: PMC9588769 DOI: 10.1038/s41467-022-33992-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/07/2022] [Indexed: 12/03/2022] Open
Abstract
The observation of spinon excitations in the [Formula: see text] triangular antiferromagnet Ca3ReO5Cl2 reveals a quasi-one-dimensional (1D) nature of magnetic correlations, in spite of the nominally 2D magnetic structure. This phenomenon is known as frustration-induced dimensional reduction. Here, we present high-field electron spin resonance spectroscopy and magnetization studies of Ca3ReO5Cl2, allowing us not only to refine spin-Hamiltonian parameters, but also to investigate peculiarities of its low-energy spin dynamics. We argue that the presence of the uniform Dzyaloshinskii-Moriya interaction (DMI) shifts the spinon continuum in momentum space and, as a result, opens a zero-field gap at the Γ point. We observed this gap directly. The shift is found to be consistent with the structural modulation in the ordered state, suggesting this material as a perfect model triangular-lattice system, where a pure DMI-spiral ground state can be realized.
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Affiliation(s)
- S. A. Zvyagin
- Dresden High Magnetic Field Laboratory (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - A. N. Ponomaryov
- Dresden High Magnetic Field Laboratory (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
- Present Address: Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - J. Wosnitza
- Dresden High Magnetic Field Laboratory (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
- Institut für Festkörper- und Materialphysik, TU Dresden, 01062 Dresden, Germany
| | - D. Hirai
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - Z. Hiroi
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - M. Gen
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - Y. Kohama
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - A. Matsuo
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - Y. H. Matsuda
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - K. Kindo
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 Japan
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19
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Nawa K, Avdeev M, Berdonosov P, Sobolev A, Presniakov I, Aslandukova A, Kozlyakova E, Vasiliev A, Shchetinin I, Sato TJ. Magnetic structure study of the sawtooth chain antiferromagnet [Formula: see text]. Sci Rep 2021; 11:24049. [PMID: 34912012 PMCID: PMC8674342 DOI: 10.1038/s41598-021-03058-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 11/23/2021] [Indexed: 11/22/2022] Open
Abstract
A magnetic structure of the sawtooth-chain antiferromagnet [Formula: see text] was investigated by magnetization measurements, single crystalline and powder neutron diffraction experiments, and a further analysis on the Mössbauer spectra. These experiments revealed a nearly collinear antiferromagnetic structure with magnetic moments aligned along the b-axis, indicating dominant antiferromagnetic exchanges between Fe(1)-Fe(2) and Fe(2)-Fe(3) sites. The magnon dispersion relation derived from the linear spin wave approximation suggests the possible flat band nature of magnons.
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Affiliation(s)
- Kazuhiro Nawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Sendai, 980-8577 Japan
| | - Maxim Avdeev
- Australian Centre for Neutron Research, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW 2232 Australia
- School of Chemistry, The University of Sydney, Sydney, 2006 Australia
| | - Peter Berdonosov
- National University of Science and Technology MISIS, Moscow, 119049 Russia
- Lomonosov Moscow State University, Moscow, 119991 Russia
| | - Alexey Sobolev
- Lomonosov Moscow State University, Moscow, 119991 Russia
| | | | - Alena Aslandukova
- Lomonosov Moscow State University, Moscow, 119991 Russia
- Bavarian Research Institute of Experimental Geochemistry and Geophysics, University of Bayreuth, Bayreuth, 95447 Germany
| | - Ekaterina Kozlyakova
- National University of Science and Technology MISIS, Moscow, 119049 Russia
- Lomonosov Moscow State University, Moscow, 119991 Russia
| | - Alexander Vasiliev
- National University of Science and Technology MISIS, Moscow, 119049 Russia
- Lomonosov Moscow State University, Moscow, 119991 Russia
| | - Igor Shchetinin
- National University of Science and Technology MISIS, Moscow, 119049 Russia
| | - Taku J. Sato
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Sendai, 980-8577 Japan
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20
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Hoffmann DK, Singh VP, Paintner T, Jäger M, Limmer W, Mathey L, Hecker Denschlag J. Second sound in the crossover from the Bose-Einstein condensate to the Bardeen-Cooper-Schrieffer superfluid. Nat Commun 2021; 12:7074. [PMID: 34873169 PMCID: PMC8648831 DOI: 10.1038/s41467-021-27149-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 10/26/2021] [Indexed: 11/28/2022] Open
Abstract
Second sound is an entropy wave which propagates in the superfluid component of a quantum liquid. Because it is an entropy wave, it probes the thermodynamic properties of the quantum liquid. Here, we study second sound propagation for a large range of interaction strengths within the crossover between a Bose-Einstein condensate (BEC) and the Bardeen-Cooper-Schrieffer (BCS) superfluid, extending previous work at unitarity. In particular, we investigate the strongly-interacting regime where currently theoretical predictions only exist in terms of an interpolation in the crossover. Working with a quantum gas of ultracold fermionic 6Li atoms with tunable interactions, we show that the second sound speed varies only slightly in the crossover regime. By varying the excitation procedure, we gain deeper insight on sound propagation. We compare our measurement results with classical-field simulations, which help with the interpretation of our experiments.
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Affiliation(s)
- Daniel K Hoffmann
- Institut für Quantenmaterie and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, D-89069, Ulm, Germany
| | - Vijay Pal Singh
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstraße 2, 30167, Hannover, Germany
- Institut für Laserphysik, Zentrum für Optische Quantentechnologien, Universität Hamburg, 22761, Hamburg, Germany
| | - Thomas Paintner
- Institut für Quantenmaterie and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, D-89069, Ulm, Germany
| | - Manuel Jäger
- Institut für Quantenmaterie and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, D-89069, Ulm, Germany
| | - Wolfgang Limmer
- Institut für Quantenmaterie and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, D-89069, Ulm, Germany
| | - Ludwig Mathey
- Institut für Laserphysik, Zentrum für Optische Quantentechnologien, Universität Hamburg, 22761, Hamburg, Germany
- The Hamburg center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Johannes Hecker Denschlag
- Institut für Quantenmaterie and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, D-89069, Ulm, Germany.
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21
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Tomarchio L, Macis S, Mosesso L, Nguyen LT, Grilli A, Guidi MC, Cava RJ, Lupi S. Low energy electrodynamics of CrI(3) layered ferromagnet. Sci Rep 2021; 11:23405. [PMID: 34862444 DOI: 10.1038/s41598-021-02918-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 11/16/2021] [Indexed: 11/09/2022] Open
Abstract
We report on the optical properties from terahertz (THz) to Near-Infrared (NIR) of the layered magnetic compound CrI3 at various temperatures, both in the paramagnetic and ferromagnetic phase. In the NIR spectral range, we observe an insulating electronic gap around 1.1 eV which strongly hardens with decreasing temperature. The blue shift observed represents a record in insulating materials and it is a fingerprint of a strong electron-phonon interaction. Moreover, a further gap hardening is observed below the Curie temperature, indicating the establishment of an effective interaction between electrons and magnetic degrees of freedom in the ferromagnetic phase. Similar interactions are confirmed by the disappearance of some phonon modes in the same phase, as expected from a spin-lattice interaction theory. Therefore, the optical properties of CrI3 reveal a complex interaction among electronic, phononic and magnetic degrees of freedom, opening many possibilities for its use in 2-Dimensional heterostructures.
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22
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Wang S, Choubey P, Chong YX, Chen W, Ren W, Eisaki H, Uchida S, Hirschfeld PJ, Davis JCS. Scattering interference signature of a pair density wave state in the cuprate pseudogap phase. Nat Commun 2021; 12:6087. [PMID: 34667154 PMCID: PMC8526682 DOI: 10.1038/s41467-021-26028-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 09/09/2021] [Indexed: 11/21/2022] Open
Abstract
An unidentified quantum fluid designated the pseudogap (PG) phase is produced by electron-density depletion in the CuO2 antiferromagnetic insulator. Current theories suggest that the PG phase may be a pair density wave (PDW) state characterized by a spatially modulating density of electron pairs. Such a state should exhibit a periodically modulating energy gap [Formula: see text] in real-space, and a characteristic quasiparticle scattering interference (QPI) signature [Formula: see text] in wavevector space. By studying strongly underdoped Bi2Sr2CaDyCu2O8 at hole-density ~0.08 in the superconductive phase, we detect the 8a0-periodic [Formula: see text] modulations signifying a PDW coexisting with superconductivity. Then, by visualizing the temperature dependence of this electronic structure from the superconducting into the pseudogap phase, we find the evolution of the scattering interference signature [Formula: see text] that is predicted specifically for the temperature dependence of an 8a0-periodic PDW. These observations are consistent with theory for the transition from a PDW state coexisting with d-wave superconductivity to a pure PDW state in the Bi2Sr2CaDyCu2O8 pseudogap phase.
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Affiliation(s)
- Shuqiu Wang
- Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Peayush Choubey
- Institut für Theoretische Physik III, Ruhr-Universität Bochum, Bochum, Germany
- Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, India
| | - Yi Xue Chong
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA
| | - Weijiong Chen
- Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Wangping Ren
- Clarendon Laboratory, University of Oxford, Oxford, UK
| | - H Eisaki
- Institute of Advanced Industrial Science and Tech., Tsukuba, Ibaraki, Japan
| | - S Uchida
- Institute of Advanced Industrial Science and Tech., Tsukuba, Ibaraki, Japan
| | | | - J C Séamus Davis
- Clarendon Laboratory, University of Oxford, Oxford, UK.
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA.
- Department of Physics, University College Cork, Cork, Ireland.
- Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany.
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23
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Abstract
Floquet engineering uses coherent time-periodic drives to realize designer band structures on-demand, thus yielding a versatile approach for inducing a wide range of exotic quantum many-body phenomena. Here we show how this approach can be used to induce non-equilibrium correlated states with spontaneously broken symmetry in lightly doped semiconductors. In the presence of a resonant driving field, the system spontaneously develops quantum liquid crystalline order featuring strong anisotropy whose directionality rotates as a function of time. The phase transition occurs in the steady state of the system achieved due to the interplay between the coherent external drive, electron-electron interactions, and dissipative processes arising from the coupling to phonons and the electromagnetic environment. We obtain the phase diagram of the system using numerical calculations that match predictions obtained from a phenomenological treatment and discuss the conditions on the system and the external drive under which spontaneous symmetry breaking occurs. Our results demonstrate that coherent driving can be used to induce non-equilibrium quantum phases of matter with dynamical broken symmetry.
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Affiliation(s)
- Iliya Esin
- Physics Department, Technion, Haifa, Israel.
- Department of Physics, California Institute of Technology, Pasadena, CA, USA.
| | | | - Erez Berg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Mark S Rudner
- Center for Quantum Devices and Niels Bohr International Academy, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
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24
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Wang S, Yoo S, Zhao S, Zhao W, Kahn S, Cui D, Wu F, Jiang L, Utama MIB, Li H, Li S, Zibrov A, Regan E, Wang D, Zhang Z, Watanabe K, Taniguchi T, Zhou C, Wang F. Gate-tunable plasmons in mixed-dimensional van der Waals heterostructures. Nat Commun 2021; 12:5039. [PMID: 34413291 PMCID: PMC8376888 DOI: 10.1038/s41467-021-25269-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 07/14/2021] [Indexed: 11/09/2022] Open
Abstract
Surface plasmons, collective electromagnetic excitations coupled to conduction electron oscillations, enable the manipulation of light-matter interactions at the nanoscale. Plasmon dispersion of metallic structures depends sensitively on their dimensionality and has been intensively studied for fundamental physics as well as applied technologies. Here, we report possible evidence for gate-tunable hybrid plasmons from the dimensionally mixed coupling between one-dimensional (1D) carbon nanotubes and two-dimensional (2D) graphene. In contrast to the carrier density-independent 1D Luttinger liquid plasmons in bare metallic carbon nanotubes, plasmon wavelengths in the 1D-2D heterostructure are modulated by 75% via electrostatic gating while retaining the high figures of merit of 1D plasmons. We propose a theoretical model to describe the electromagnetic interaction between plasmons in nanotubes and graphene, suggesting plasmon hybridization as a possible origin for the observed large plasmon modulation. The mixed-dimensional plasmonic heterostructures may enable diverse designs of tunable plasmonic nanodevices.
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Affiliation(s)
- Sheng Wang
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA.
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - SeokJae Yoo
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA.
- Department of Physics, Korea University, Seoul, Korea.
| | - Sihan Zhao
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
| | - Wenyu Zhao
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
| | - Salman Kahn
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
| | - Dingzhou Cui
- Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
| | - Fanqi Wu
- Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
| | - Lili Jiang
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
| | - M Iqbal Bakti Utama
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California at Berkeley, Berkeley, CA, USA
| | - Hongyuan Li
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
- Graduate Group in Applied Science and Technology, University of California at Berkeley, Berkeley, CA, USA
| | - Shaowei Li
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Alexander Zibrov
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Emma Regan
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Graduate Group in Applied Science and Technology, University of California at Berkeley, Berkeley, CA, USA
| | - Danqing Wang
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Graduate Group in Applied Science and Technology, University of California at Berkeley, Berkeley, CA, USA
| | - Zuocheng Zhang
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Chongwu Zhou
- Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
- Department of Electrical Engineering, University of Southern California, Los Angeles, CA, USA
| | - Feng Wang
- Department of Physics, University of California at Berkeley, Berkeley, CA, USA.
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Kavli Energy NanoScience Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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25
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Li H, Zhang HK, Wang J, Wu HQ, Gao Y, Qu DW, Liu ZX, Gong SS, Li W. Identification of magnetic interactions and high-field quantum spin liquid in α-RuCl 3. Nat Commun 2021; 12:4007. [PMID: 34188044 PMCID: PMC8242101 DOI: 10.1038/s41467-021-24257-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 06/07/2021] [Indexed: 11/15/2022] Open
Abstract
The frustrated magnet α-RuCl3 constitutes a fascinating quantum material platform that harbors the intriguing Kitaev physics. However, a consensus on its intricate spin interactions and field-induced quantum phases has not been reached yet. Here we exploit multiple state-of-the-art many-body methods and determine the microscopic spin model that quantitatively explains major observations in α-RuCl3, including the zigzag order, double-peak specific heat, magnetic anisotropy, and the characteristic M-star dynamical spin structure, etc. According to our model simulations, the in-plane field drives the system into the polarized phase at about 7 T and a thermal fractionalization occurs at finite temperature, reconciling observations in different experiments. Under out-of-plane fields, the zigzag order is suppressed at 35 T, above which, and below a polarization field of 100 T level, there emerges a field-induced quantum spin liquid. The fractional entropy and algebraic low-temperature specific heat unveil the nature of a gapless spin liquid, which can be explored in high-field measurements on α-RuCl3.
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Affiliation(s)
- Han Li
- School of Physics, Beihang University, Beijing, China
| | - Hao-Kai Zhang
- School of Physics, Beihang University, Beijing, China
- Institute for Advanced Study, Tsinghua University, Beijing, China
| | - Jiucai Wang
- Institute for Advanced Study, Tsinghua University, Beijing, China
- Department of Physics, Renmin University of China, Beijing, China
| | - Han-Qing Wu
- Center for Neutron Science and Technology, School of Physics, Sun Yat-sen University, Guangzhou, China
| | - Yuan Gao
- School of Physics, Beihang University, Beijing, China
| | - Dai-Wei Qu
- School of Physics, Beihang University, Beijing, China
| | - Zheng-Xin Liu
- Department of Physics, Renmin University of China, Beijing, China.
| | - Shou-Shu Gong
- School of Physics, Beihang University, Beijing, China.
- International Research Institute of Multidisciplinary Science, Beihang University, Beijing, China.
| | - Wei Li
- School of Physics, Beihang University, Beijing, China.
- International Research Institute of Multidisciplinary Science, Beihang University, Beijing, China.
- Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, China.
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26
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Li H, Zhang TT, Said A, Fabbris G, Mazzone DG, Yan JQ, Mandrus D, Halász GB, Okamoto S, Murakami S, Dean MPM, Lee HN, Miao H. Giant phonon anomalies in the proximate Kitaev quantum spin liquid α-RuCl 3. Nat Commun 2021; 12:3513. [PMID: 34112804 PMCID: PMC8192767 DOI: 10.1038/s41467-021-23826-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 04/30/2021] [Indexed: 11/18/2022] Open
Abstract
The Kitaev quantum spin liquid epitomizes an entangled topological state, for which two flavors of fractionalized low-energy excitations are predicted: the itinerant Majorana fermion and the Z2 gauge flux. It was proposed recently that fingerprints of fractional excitations are encoded in the phonon spectra of Kitaev quantum spin liquids through a novel fractional-excitation-phonon coupling. Here, we detect anomalous phonon effects in α-RuCl3 using inelastic X-ray scattering with meV resolution. At high temperature, we discover interlaced optical phonons intercepting a transverse acoustic phonon between 3 and 7 meV. Upon decreasing temperature, the optical phonons display a large intensity enhancement near the Kitaev energy, JK~8 meV, that coincides with a giant acoustic phonon softening near the Z2 gauge flux energy scale. These phonon anomalies signify the coupling of phonon and Kitaev magnetic excitations in α-RuCl3 and demonstrates a proof-of-principle method to detect anomalous excitations in topological quantum materials.
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Affiliation(s)
- Haoxiang Li
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - T T Zhang
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
- Tokodai Institute for Element Strategy, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Kanagawa, Japan
| | - A Said
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - G Fabbris
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - D G Mazzone
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, Villigen, Switzerland
| | - J Q Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - D Mandrus
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Materials Science and Engineering, the University of Tennessee at Knoxville, Knoxville, TN, USA
| | - Gábor B Halász
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - S Okamoto
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - S Murakami
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
- Tokodai Institute for Element Strategy, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Kanagawa, Japan
| | - M P M Dean
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - H Miao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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27
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Abstract
Confinement describes the phenomenon when the attraction between two particles grows with their distance, most prominently found in quantum chromodynamics (QCD) between quarks. In condensed matter physics, confinement can appear in quantum spin chains, for example, in the one dimensional transverse field Ising model (TFIM) with an additional longitudinal field, famously observed in the quantum material cobalt niobate or in optical lattices. Here, we establish that state-of-the-art quantum computers have reached capabilities to simulate confinement physics in spin chains. We report quantitative confinement signatures of the TFIM on an IBM quantum computer observed via two distinct velocities for information propagation from domain walls and their mesonic bound states. We also find the confinement induced slow down of entanglement spreading by implementing randomized measurement protocols for the second order Rényi entanglement entropy. Our results are a crucial step for probing non-perturbative interacting quantum phenomena on digital quantum computers beyond the capabilities of classical hardware.
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Affiliation(s)
- Joseph Vovrosh
- Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK
| | - Johannes Knolle
- Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK.
- Department of Physics TQM, Technische Universität München, James-Franck-Straße 1, 85748, Garching, Germany.
- Munich Center for Quantum Science and Technology (MCQST), 80799, Munich, Germany.
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28
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Valentinis D, Zaanen J, van der Marel D. Propagation of shear stress in strongly interacting metallic Fermi liquids enhances transmission of terahertz radiation. Sci Rep 2021; 11:7105. [PMID: 33782440 PMCID: PMC8007721 DOI: 10.1038/s41598-021-86356-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 03/15/2021] [Indexed: 11/09/2022] Open
Abstract
A highlight of Fermi-liquid phenomenology, as explored in neutral [Formula: see text]He, is the observation that in the collisionless regime shear stress propagates as if one is dealing with the transverse phonon of a solid. The existence of this "transverse zero sound" requires that the quasiparticle mass enhancement exceeds a critical value. Could such a propagating shear stress also exist in strongly correlated electron systems? Despite some noticeable differences with the neutral case in the Galilean continuum, we arrive at the verdict that transverse zero sound should be generic for mass enhancement higher than 3. We present an experimental setup that should be exquisitely sensitive in this regard: the transmission of terahertz radiation through a thin slab of heavy-fermion material will be strongly enhanced at low temperature and accompanied by giant oscillations, which reflect the interference between light itself and the "material photon" being the actual manifestation of transverse zero sound in the charged Fermi liquid.
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Affiliation(s)
- D Valentinis
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211, Geneva 4, Switzerland
- Institute for Theoretical Condensed Matter Physics, Karlsruhe Institute of Technology, Wolfgang-Gaede Straße 1, 76131, Karlsruhe, Germany
| | - J Zaanen
- Institute-Lorentz for Theoretical Physics, Leiden University, PO Box 9506, 2300 RA, Leiden, The Netherlands
| | - D van der Marel
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211, Geneva 4, Switzerland.
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29
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Bretscher HM, Andrich P, Telang P, Singh A, Harnagea L, Sood AK, Rao A. Ultrafast melting and recovery of collective order in the excitonic insulator Ta 2NiSe 5. Nat Commun 2021; 12:1699. [PMID: 33727541 PMCID: PMC7966769 DOI: 10.1038/s41467-021-21929-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 02/08/2021] [Indexed: 01/05/2023] Open
Abstract
The layered chalcogenide Ta2NiSe5 has been proposed to host an excitonic condensate in its ground state, a phase that could offer a unique platform to study and manipulate many-body states at room temperature. However, identifying the dominant microscopic contribution to the observed spontaneous symmetry breaking remains challenging, perpetuating the debate over the ground state properties. Here, using broadband ultrafast spectroscopy we investigate the out-of-equilibrium dynamics of Ta2NiSe5 and demonstrate that the transient reflectivity in the near-infrared range is connected to the system's low-energy physics. We track the status of the ordered phase using this optical signature, establishing that high-fluence photoexcitations can suppress this order. From the sub-50 fs quenching timescale and the behaviour of the photoinduced coherent phonon modes, we conclude that electronic correlations provide a decisive contribution to the excitonic order formation. Our results pave the way towards the ultrafast control of an exciton condensate at room temperature.
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Affiliation(s)
| | - Paolo Andrich
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| | - Prachi Telang
- Department of Physics, Indian Institute of Science Education and Research, Pune, Maharashtra, India
| | - Anupam Singh
- Department of Physics, Indian Institute of Science Education and Research, Pune, Maharashtra, India
| | - Luminita Harnagea
- Department of Physics, Indian Institute of Science Education and Research, Pune, Maharashtra, India
| | - A K Sood
- Department of Physics, Indian Institute of Science, Bangalore, Karnataka, India
| | - Akshay Rao
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
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30
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Galeski S, Zhao X, Wawrzyńczak R, Meng T, Förster T, Lozano PM, Honnali S, Lamba N, Ehmcke T, Markou A, Li Q, Gu G, Zhu W, Wosnitza J, Felser C, Chen GF, Gooth J. Unconventional Hall response in the quantum limit of HfTe 5. Nat Commun 2020; 11:5926. [PMID: 33230118 PMCID: PMC7683529 DOI: 10.1038/s41467-020-19773-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/21/2020] [Indexed: 11/18/2022] Open
Abstract
Interacting electrons confined to their lowest Landau level in a high magnetic field can form a variety of correlated states, some of which manifest themselves in a Hall effect. Although such states have been predicted to occur in three-dimensional semimetals, a corresponding Hall response has not yet been experimentally observed. Here, we report the observation of an unconventional Hall response in the quantum limit of the bulk semimetal HfTe5, adjacent to the three-dimensional quantum Hall effect of a single electron band at low magnetic fields. The additional plateau-like feature in the Hall conductivity of the lowest Landau level is accompanied by a Shubnikov-de Haas minimum in the longitudinal electrical resistivity and its magnitude relates as 3/5 to the height of the last plateau of the three-dimensional quantum Hall effect. Our findings are consistent with strong electron-electron interactions, stabilizing an unconventional variant of the Hall effect in a three-dimensional material in the quantum limit.
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Affiliation(s)
- S Galeski
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
| | - X Zhao
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, 523808, Dongguan, Guangdong, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - R Wawrzyńczak
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - T Meng
- Institute of Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062, Dresden, Germany
| | - T Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - P M Lozano
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - S Honnali
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - N Lamba
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - T Ehmcke
- Institute of Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062, Dresden, Germany
| | - A Markou
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - Q Li
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - W Zhu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - J 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
| | - C Felser
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - G F Chen
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, 523808, Dongguan, Guangdong, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - J Gooth
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany.
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31
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Kora Y, Boninsegni M, Son DT, Zhang S. Tuning the quantumness of simple Bose systems: A universal phase diagram. Proc Natl Acad Sci U S A 2020; 117:27231-7. [PMID: 33087572 DOI: 10.1073/pnas.2017646117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We present a comprehensive theoretical study of the phase diagram of a system of many Bose particles interacting with a two-body central potential of the so-called Lennard-Jones form. First-principles path-integral computations are carried out, providing essentially exact numerical results on the thermodynamic properties. The theoretical model used here provides a realistic and remarkably general framework for describing simple Bose systems ranging from crystals to normal fluids to superfluids and gases. The interplay between particle interactions on the one hand and quantum indistinguishability and delocalization on the other hand is characterized by a single quantumness parameter, which can be tuned to engineer and explore different regimes. Taking advantage of the rare combination of the versatility of the many-body Hamiltonian and the possibility for exact computations, we systematically investigate the phases of the systems as a function of pressure (P) and temperature (T), as well as the quantumness parameter. We show how the topology of the phase diagram evolves from the known case of 4He, as the system is made more (and less) quantum, and compare our predictions with available results from mean-field theory. Possible realization and observation of the phases and physical regimes predicted here are discussed in various experimental systems, including hypothetical muonic matter.
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32
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Lotnyk D, Eyal A, Zhelev N, Abhilash TS, Smith EN, Terilli M, Wilson J, Mueller E, Einzel D, Saunders J, Parpia JM. Thermal transport of helium-3 in a strongly confining channel. Nat Commun 2020; 11:4843. [PMID: 32973182 PMCID: PMC7515880 DOI: 10.1038/s41467-020-18662-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 09/02/2020] [Indexed: 11/09/2022] Open
Abstract
The investigation of transport properties in normal liquid helium-3 and its topological superfluid phases provides insights into related phenomena in electron fluids, topological materials, and putative topological superconductors. It relies on the measurement of mass, heat, and spin currents, due to system neutrality. Of particular interest is transport in strongly confining channels of height approaching the superfluid coherence length, to enhance the relative contribution of surface excitations, and suppress hydrodynamic counterflow. Here we report on the thermal conduction of helium-3 in a 1.1 μm high channel. In the normal state we observe a diffusive thermal conductivity that is approximately temperature independent, consistent with interference of bulk and boundary scattering. In the superfluid, the thermal conductivity is only weakly temperature dependent, requiring detailed theoretical analysis. An anomalous thermal response is detected in the superfluid which we propose arises from the emission of a flux of surface excitations from the channel.
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Affiliation(s)
- D Lotnyk
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - A Eyal
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
- Physics Department, Technion, Haifa, Israel
| | - N Zhelev
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - T S Abhilash
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - E N Smith
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - M Terilli
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - J Wilson
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
- SUNY Geneseo, Geneseo, NY, 14454, USA
| | - E Mueller
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA
| | - D Einzel
- Walther Meissner Institut, Garching, Germany
| | - J Saunders
- Department of Physics, Royal Holloway University of London, Egham, TW20 0EX, Surrey, UK
| | - J M Parpia
- Department of Physics, Cornell University, Ithaca, NY, 14853, USA.
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33
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Autti S, Ahlstrom SL, Haley RP, Jennings A, Pickett GR, Poole M, Schanen R, Soldatov AA, Tsepelin V, Vonka J, Wilcox T, Woods AJ, Zmeev DE. Fundamental dissipation due to bound fermions in the zero-temperature limit. Nat Commun 2020; 11:4742. [PMID: 32958764 PMCID: PMC7506006 DOI: 10.1038/s41467-020-18499-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 08/26/2020] [Indexed: 11/12/2022] Open
Abstract
The ground state of a fermionic condensate is well protected against perturbations in the presence of an isotropic gap. Regions of gap suppression, surfaces and vortex cores which host Andreev-bound states, seemingly lift that strict protection. Here we show that in superfluid 3He the role of bound states is more subtle: when a macroscopic object moves in the superfluid at velocities exceeding the Landau critical velocity, little to no bulk pair breaking takes place, while the damping observed originates from the bound states covering the moving object. We identify two separate timescales that govern the bound state dynamics, one of them much longer than theoretically anticipated, and show that the bound states do not interact with bulk excitations.
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Affiliation(s)
- S Autti
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK.
| | - S L Ahlstrom
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - R P Haley
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - A Jennings
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - G R Pickett
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - M Poole
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - R Schanen
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - A A Soldatov
- P.L. Kapitza Institute for Physical Problems of RAS, Moscow, 119334, Russia
| | - V Tsepelin
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - J Vonka
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - T Wilcox
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - A J Woods
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
- Department of Physics and NHMFL High B/T Facility, University of Florida, Gainesville, FL, 32611, USA
| | - D E Zmeev
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
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34
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Di Sante D, Erdmenger J, Greiter M, Matthaiakakis I, Meyer R, Fernández DR, Thomale R, van Loon E, Wehling T. Turbulent hydrodynamics in strongly correlated Kagome metals. Nat Commun 2020; 11:3997. [PMID: 32778647 PMCID: PMC7417536 DOI: 10.1038/s41467-020-17663-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/14/2020] [Indexed: 11/26/2022] Open
Abstract
A current challenge in condensed matter physics is the realization of strongly correlated, viscous electron fluids. These fluids can be described by holography, that is, by mapping them onto a weakly curved gravitational theory via gauge/gravity duality. The canonical system considered for realizations has been graphene. In this work, we show that Kagome systems with electron fillings adjusted to the Dirac nodes provide a much more compelling platform for realizations of viscous electron fluids, including non-linear effects such as turbulence. In particular, we find that in Scandium Herbertsmithite, the fine-structure constant, which measures the effective Coulomb interaction, is enhanced by a factor of about 3.2 as compared to graphene. We employ holography to estimate the ratio of the shear viscosity over the entropy density in Sc-Herbertsmithite, and find it about three times smaller than in graphene. These findings put the turbulent flow regime described by holography within the reach of experiments.
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Affiliation(s)
- Domenico Di Sante
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Johanna Erdmenger
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Martin Greiter
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Ioannis Matthaiakakis
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - René Meyer
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - David Rodríguez Fernández
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Ronny Thomale
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
| | - Erik van Loon
- Institut für Theoretische Physik, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
| | - Tim Wehling
- Institut für Theoretische Physik, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
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35
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Fujihala M, Morita K, Mole R, Mitsuda S, Tohyama T, Yano SI, Yu D, Sota S, Kuwai T, Koda A, Okabe H, Lee H, Itoh S, Hawai T, Masuda T, Sagayama H, Matsuo A, Kindo K, Ohira-Kawamura S, Nakajima K. Gapless spin liquid in a square-kagome lattice antiferromagnet. Nat Commun 2020; 11:3429. [PMID: 32647219 PMCID: PMC7347939 DOI: 10.1038/s41467-020-17235-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 06/19/2020] [Indexed: 11/29/2022] Open
Abstract
Observation of a quantum spin liquid (QSL) state is one of the most important goals in condensed-matter physics, as well as the development of new spintronic devices that support next-generation industries. The QSL in two dimensional quantum spin systems is expected to be due to geometrical magnetic frustration, and thus a kagome-based lattice is the most probable playground for QSL. Here, we report the first experimental results of the QSL state on a square-kagome quantum antiferromagnet, KCu6AlBiO4(SO4)5Cl. Comprehensive experimental studies via magnetic susceptibility, magnetisation, heat capacity, muon spin relaxation (μSR), and inelastic neutron scattering (INS) measurements reveal the formation of a gapless QSL at very low temperatures close to the ground state. The QSL behavior cannot be explained fully by a frustrated Heisenberg model with nearest-neighbor exchange interactions, providing a theoretical challenge to unveil the nature of the QSL state.
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Affiliation(s)
- Masayoshi Fujihala
- Tokyo University of Science, Department of Physics, Tokyo, 162-8601, Japan.
| | - Katsuhiro Morita
- Tokyo University of Science, Department of Applied Physics, Tokyo, 125-8585, Japan.
| | - Richard Mole
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, 2232, Australia
| | - Setsuo Mitsuda
- Tokyo University of Science, Department of Physics, Tokyo, 162-8601, Japan
| | - Takami Tohyama
- Tokyo University of Science, Department of Applied Physics, Tokyo, 125-8585, Japan
| | - Shin-Ichiro Yano
- National Synchrotron Radiation Research Center, Hsinchu, 30077, Taiwan
| | - Dehong Yu
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, 2232, Australia
| | - Shigetoshi Sota
- Computational Materials Science Research Team, RIKEN Center for Computational Science, Kobe, Hyogo, 650-0047, Japan
| | - Tomohiko Kuwai
- Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555, Japan
| | - Akihiro Koda
- Muon Science Laboratory and Condensed Matter Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organisation, 1-1 Oho, Tsukuba, 305-0801, Japan
| | - Hirotaka Okabe
- Muon Science Laboratory and Condensed Matter Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organisation, 1-1 Oho, Tsukuba, 305-0801, Japan
| | - Hua Lee
- Muon Science Laboratory and Condensed Matter Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organisation, 1-1 Oho, Tsukuba, 305-0801, Japan
| | - Shinichi Itoh
- Neutron Science Division, Institute of Materials Structure Science, High Energy Accelerator Research Organisation, 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan
| | - Takafumi Hawai
- Neutron Science Division, Institute of Materials Structure Science, High Energy Accelerator Research Organisation, 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan
| | - Takatsugu Masuda
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Hajime Sagayama
- Synchrotron Radiation Science Division 1 and Center for Integrative Quantum Beam Science, Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan
| | - Akira Matsuo
- International MegaGauss Science Laboratory, Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Koichi Kindo
- International MegaGauss Science Laboratory, Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Seiko Ohira-Kawamura
- Materials and Life Science Division, J-PARC Center, Tokai, Ibaraki, 319-1195, Japan
| | - Kenji Nakajima
- Materials and Life Science Division, J-PARC Center, Tokai, Ibaraki, 319-1195, Japan
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36
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Diniz PC, Oliveira EAB, Lima ARP, Henn EAL. Ground state and collective excitations of a dipolar Bose-Einstein condensate in a bubble trap. Sci Rep 2020; 10:4831. [PMID: 32179828 PMCID: PMC7075965 DOI: 10.1038/s41598-020-61657-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 02/24/2020] [Indexed: 11/09/2022] Open
Abstract
We consider the ground state and the collective excitations of dipolar Bose-Einstein condensates in a bubble trap, i.e., a shell-shaped spherically symmetric confining potential. By means of an appropriate Gaussian ansatz, we determine the ground-state properties in the case where the particles interact by means of both the isotropic and short-range contact and the anisotropic and long-range dipole-dipole potential in the thin-shell limit. Moreover, with the ground state at hand, we employ the sum-rule approach to study the monopole, the two-, the three-dimensional quadrupole as well as the dipole modes. We find situations in which neither the virial nor Kohn's theorem can be applied. On top of that, we demonstrate the existence of anisotropic particle density profiles, which are absent in the case with repulsive contact interaction only. These significant deviations from what one would typically expect are then traced back to both the anisotropic nature of the dipolar interaction and the novel topology introduced by the bubble trap.
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Affiliation(s)
- Pedro C Diniz
- São Carlos Institute of Physics, University of São Paulo, PO Box 369, 13560-970, São Carlos, SP, Brazil
| | - Eduardo A B Oliveira
- São Carlos Institute of Physics, University of São Paulo, PO Box 369, 13560-970, São Carlos, SP, Brazil
| | - Aristeu R P Lima
- Universidade da Integração Internacional da Lusofonia Afro-Brasileira, Campus das Auroras, Acarape-Ceará, Brazil.
| | - Emanuel A L Henn
- São Carlos Institute of Physics, University of São Paulo, PO Box 369, 13560-970, São Carlos, SP, Brazil.
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37
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Canella GA, França VV. Superfluid-Insulator Transition unambiguously detected by entanglement in one-dimensional disordered superfluids. Sci Rep 2019; 9:15313. [PMID: 31653967 PMCID: PMC6814829 DOI: 10.1038/s41598-019-51986-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 10/11/2019] [Indexed: 11/17/2022] Open
Abstract
We use entanglement to track the superfluid-insulator transition (SIT) in disordered fermionic superfluids described by the one-dimensional Hubbard model. Entanglement is found to have remarkable signatures of the SIT driven by i) the disorder strength V, ii) the concentration of impurities C and iii) the particle density n. Our results reveal the absence of a critical potential intensity on the SIT driven by V, i.e. any small V suffices to decrease considerably the degree of entanglement: it drops ∼50% for V = -0.25t. We also find that entanglement is non-monotonic with the concentration C, approaching to zero for a certain critical value CC. This critical concentration is found to be related to a special type of localization, here named as fully-localized state, which can be also reached for a particular density nC. Our results show that the SIT driven by n or C has distinct nature whether it leads to the full localization or to the ordinary one: it is a first-order quantum phase transition only when leading to full localization. In contrast, the SIT driven by V is never a first-order quantum phase transition independently on the type of localization reached.
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Affiliation(s)
- G A Canella
- Institute of Chemistry, São Paulo State University, 14800-090, Araraquara, São Paulo, Brazil
| | - V V França
- Institute of Chemistry, São Paulo State University, 14800-090, Araraquara, São Paulo, Brazil.
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38
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Weiss LS, Borgh MO, Blinova A, Ollikainen T, Möttönen M, Ruostekoski J, Hall DS. Controlled creation of a singular spinor vortex by circumventing the Dirac belt trick. Nat Commun 2019; 10:4772. [PMID: 31619679 PMCID: PMC6795882 DOI: 10.1038/s41467-019-12787-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 10/01/2019] [Indexed: 11/18/2022] Open
Abstract
Persistent topological defects and textures are particularly dramatic consequences of superfluidity. Among the most fascinating examples are the singular vortices arising from the rotational symmetry group SO(3), with surprising topological properties illustrated by Dirac's famous belt trick. Despite considerable interest, controlled preparation and detailed study of vortex lines with complex internal structure in fully three-dimensional spinor systems remains an outstanding experimental challenge. Here, we propose and implement a reproducible and controllable method for creating and detecting a singular SO(3) line vortex from the decay of a non-singular spin texture in a ferromagnetic spin-1 Bose-Einstein condensate. Our experiment explicitly demonstrates the SO(3) character and the unique spinor properties of the defect. Although the vortex is singular, its core fills with atoms in the topologically distinct polar magnetic phase. The resulting stable, coherent topological interface has analogues in systems ranging from condensed matter to cosmology and string theory.
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Affiliation(s)
- L S Weiss
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA
- Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD, 20723, USA
| | - M O Borgh
- Faculty of Science, University of East Anglia, Norwich, NR4 7TJ, UK
| | - A Blinova
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA
- Department of Physics, University of Massachusetts, Amherst, MA, 01003, USA
| | - T Ollikainen
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA
- QCD Labs, QTF Centre of Excellence, Department of Applied Physics, Aalto University, P.O. Box 13500, FI-00076, Aalto, Finland
| | - M Möttönen
- QCD Labs, QTF Centre of Excellence, Department of Applied Physics, Aalto University, P.O. Box 13500, FI-00076, Aalto, Finland
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, FI-02044, VTT, Finland
| | - J Ruostekoski
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - D S Hall
- Department of Physics and Astronomy, Amherst College, Amherst, MA, 01002-5000, USA.
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39
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Abstract
We derive the complete mixing-demixing phase-diagram relevant to a bosonic binary mixture confined in a ring trimer and modeled within the Bose-Hubbard picture. The mixing properties of the two quantum fluids, which are shown to be strongly affected by the fragmented character of the confining potential, are evaluated by means of a specific indicator imported from Statistical Thermodynamics and are shown to depend only on two effective parameters incorporating the asymmetry between the heteronuclear species. To closely match realistic experimental conditions, our study is extended also beyond the pointlike approximation of potential wells by describing the systems in terms of two coupled Gross-Pitaevskii equations. The resulting mean-field analysis confirms the rich scenario of mixing-demixing transitions of the mixture and also constitutes an effective springboard towards a viable experimental realization. We additionally propose an experimental realization based on a realistic optical-tweezers system and on the bosonic mixture 23Na + 39K, thanks to the large tunability of their intra- and inter-species scattering lengths.
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Affiliation(s)
- Andrea Richaud
- Department of Applied Science and Technology and u.d.r. CNISM, Politecnico di Torino, I-10129, Torino, Italy.
| | - Alessandro Zenesini
- Institut für Quantenoptik, Leibniz Universität Hannover, 30167, Hannover, Germany
| | - Vittorio Penna
- Department of Applied Science and Technology and u.d.r. CNISM, Politecnico di Torino, I-10129, Torino, Italy
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