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Pouget JP, Canadell E. Structural approach to charge density waves in low-dimensional systems: electronic instability and chemical bonding. Rep Prog Phys 2024; 87:026501. [PMID: 38052072 DOI: 10.1088/1361-6633/ad124f] [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] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 12/05/2023] [Indexed: 12/07/2023]
Abstract
The charge density wave (CDW) instability, usually occurring in low-dimensional metals, has been a topic of interest for longtime. However, some very fundamental aspects of the mechanism remain unclear. Recently, a plethora of new CDW materials, a substantial fraction of which is two-dimensional or even three-dimensional, has been prepared and characterised as bulk and/or single-layers. As a result, the need for revisiting the primary mechanism of the instability, based on the electron-hole instability established more than 50 years ago for quasi-one-dimensional (quasi-1D) conductors, has clearly emerged. In this work, we consider a large number of CDW materials to revisit the main concepts used in understanding the CDW instability, and emphasise the key role of the momentum dependent electron-phonon coupling in linking electronic and structural degrees of freedom. We argue that for quasi-1D systems, earlier weak coupling theories work appropriately and the energy gain due to the CDW and the concomitant periodic lattice distortion (PLD) remains primarily due to a Fermi surface nesting mechanism. However, for materials with higher dimensionality, intermediate and strong coupling regimes are generally at work and the modification of the chemical bonding network by the PLD is at the heart of the instability. We emphasise the need for a microscopic approach blending condensed matter physics concepts and state-of-the-art first-principles calculations with quite fundamental chemical bonding ideas in understanding the CDW phenomenon in these materials.
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Affiliation(s)
- Jean-Paul Pouget
- Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Enric Canadell
- Institut de Ciencia de Materials de Barcelona, ICMAB-CSIC, Campus de la UAB, 08193 Bellaterra, Spain, and Royal Academy of Sciences and Arts of Barcelona, Chemistry Section, La Rambla 115, 08002 Barcelona, Spain
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2
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Belushkin AV. Comparison of the Possibilities of Inelastic Scattering of Synchrotron Radiation and Neutrons for Studying Atomic, Molecular, and Magnetic Dynamics in Condensed Matter. CRYSTALLOGR REP+ 2022. [DOI: 10.1134/s1063774522010035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Caciuffo R, Lander GH. X-ray synchrotron radiation studies of actinide materials. J Synchrotron Radiat 2021; 28:1692-1708. [PMID: 34738923 PMCID: PMC8570219 DOI: 10.1107/s1600577521009413] [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] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/09/2021] [Indexed: 06/13/2023]
Abstract
By reviewing a selection of X-ray diffraction (XRD), resonant X-ray scattering (RXS), X-ray magnetic circular dichroism (XMCD), resonant and non-resonant inelastic scattering (RIXS, NIXS), and dispersive inelastic scattering (IXS) experiments, the potential of synchrotron radiation techniques in studying lattice and electronic structure, hybridization effects, multipolar order and lattice dynamics in actinide materials is demonstrated.
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Affiliation(s)
- Roberto Caciuffo
- European Commission, Joint Research Centre, Postfach 2340, D-76125 Karlsruhe, Germany
| | - Gerard H. Lander
- European Commission, Joint Research Centre, Postfach 2340, D-76125 Karlsruhe, Germany
- Interface Analysis Centre, School of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, United Kingdom
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4
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Roy AP, Bajaj N, Mittal R, Babu PD, Bansal D. Quasi-One-Dimensional Fermi Surface Nesting and Hidden Nesting Enable Multiple Kohn Anomalies in α-Uranium. Phys Rev Lett 2021; 126:096401. [PMID: 33750153 DOI: 10.1103/physrevlett.126.096401] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 01/20/2021] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
The topology of the Fermi surface controls the electronic response of a metal, including charge density wave (CDW) formation. A topology conducive for Fermi surface nesting (FSN) allows the electronic susceptibility χ_{0} to diverge and induce a CDW at wave vector q_{CDW}. Kohn extended the implications of FSN to show that the imaginary part of the lattice dynamical susceptibility χ_{L}^{''} also responds anomalously for all phonon branches at q_{CDW}-a phenomenon referred to as the Kohn anomaly. However, materials exhibiting multiple Kohn anomalies remain rare. Using first-principles simulations of χ_{0} and χ_{L}^{''}, and previous scattering measurements [Crummett et al., Phys. Rev. B 19, 6028 234 (1979)PRBMDO0163-1829], we show that α-uranium harbors multiple Kohn anomalies enabled by the combined effect of FSN and "hidden" nesting, i.e., nesting of electronic states above and below the Fermi surface. FSN and hidden nesting lead to a ridgelike feature in the real part of χ_{0}, allowing interatomic forces to modulate strongly and multiple Kohn anomalies to emerge. These results emphasize the importance of hidden nesting in controlling χ_{0} and χ_{L}^{''} to exploit electronic and lattice states and enable engineering of advanced materials, including topological Weyl semimetals and superconductors.
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Affiliation(s)
- Aditya Prasad Roy
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
| | - Naini Bajaj
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
| | - Ranjan Mittal
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, MH 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai, MH 400094, India
| | - Peram D Babu
- UGC-DAE Consortium for Scientific Research, Mumbai Centre, R5-Shed, BARC, Trombay, Mumbai, MH 400085, India
| | - Dipanshu Bansal
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
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5
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Kim HH, Lefrançois E, Kummer K, Fumagalli R, Brookes NB, Betto D, Nakata S, Tortora M, Porras J, Loew T, Barber ME, Braicovich L, Mackenzie AP, Hicks CW, Keimer B, Minola M, Le Tacon M. Charge Density Waves in YBa_{2}Cu_{3}O_{6.67} Probed by Resonant X-Ray Scattering under Uniaxial Compression. Phys Rev Lett 2021; 126:037002. [PMID: 33543973 DOI: 10.1103/physrevlett.126.037002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/10/2020] [Accepted: 12/14/2020] [Indexed: 06/12/2023]
Abstract
We report a comprehensive Cu L_{3}-edge resonant x-ray scattering (RXS) study of two- and three-dimensional (2D and 3D) incommensurate charge correlations in single crystals of the underdoped high-temperature superconductor YBa_{2}Cu_{3}O_{6.67} under uniaxial compression up to 1% along the two inequivalent Cu─O─Cu bond directions (a and b) in the CuO_{2} planes. We confirm the strong in-plane anisotropy of the 2D charge correlations and observe their symmetric response to pressure: pressure along a enhances correlations along b, and vice versa. Our results imply that the underlying order parameter is uniaxial. In contrast, 3D long-range charge order is only observed along b in response to compression along a. Spectroscopic RXS measurements show that the 3D charge order resides exclusively in the CuO_{2} planes and may thus be generic to the cuprates. We discuss implications of these results for models of electronic nematicity and for the interplay between charge order and superconductivity.
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Affiliation(s)
- H-H Kim
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - E Lefrançois
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - K Kummer
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
| | - R Fumagalli
- Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - N B Brookes
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
| | - D Betto
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
| | - S Nakata
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Tortora
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - J Porras
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - T Loew
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M E Barber
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany
| | - L Braicovich
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
- Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - A P Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, United Kingdom
| | - C W Hicks
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany
| | - B Keimer
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Minola
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Le Tacon
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
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Del Rio BG, González LE, González DJ. First principles study of liquid uranium at temperatures up to 2050 K. J Phys Condens Matter 2020; 32:304001. [PMID: 32163938 DOI: 10.1088/1361-648x/ab7f6f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Uranium compounds are used as fissile materials in nuclear reactors. In present day reactors the most used nuclear fuel is uranium dioxide, but in generation-IV reactors other compounds are also being considered, such as uranium carbide and uranium mononitride. Upon possible accidents where the coolant would not circulate or be lost the core of the reactor would reach very high temperatures, and therefore it is essential to understand the behaviour of the nuclear fuel under such conditions for proper risk assessment. We consider here molten metallic uranium at several temperatures ranging from 1455 to 2050 K. Even though metallic uranium is not a candidate for nuclear fuel it could nevertheless be produced due to the thermochemical instability of uranium nitride at high temperatures. We use first principles techniques to analyse the behaviour of this system and obtain basic structural and dynamic properties, as well as some thermodynamic and transport properties, including atomic diffusion and viscosity.
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Affiliation(s)
- Beatriz G Del Rio
- Departamento de Física Teórica, Universidad de Valladolid, Valladolid, Spain
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7
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Costa NC, Blommel T, Chiu WT, Batrouni G, Scalettar RT. Phonon Dispersion and the Competition between Pairing and Charge Order. Phys Rev Lett 2018; 120:187003. [PMID: 29775370 DOI: 10.1103/physrevlett.120.187003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Indexed: 06/08/2023]
Abstract
The Holstein model describes the interaction between fermions and a collection of local (dispersionless) phonon modes. In the dilute limit, the phonon degrees of freedom dress the fermions, giving rise to polaron and bipolaron formation. At higher densities, the phonons mediate collective superconducting (SC) and charge-density wave (CDW) phases. Quantum Monte Carlo (QMC) simulations have considered both these limits but have not yet focused on the physics of more general phonon spectra. Here we report QMC studies of the role of phonon dispersion on SC and CDW order in such models. We quantify the effect of finite phonon bandwidth and curvature on the critical temperature T_{cdw} for CDW order and also uncover several novel features of diagonal long-range order in the phase diagram, including a competition between charge patterns at momenta q=(π,π) and q=(0,π) which lends insight into the relationship between Fermi surface nesting and the wave vector at which charge order occurs. We also demonstrate SC order at half filling in situations where a nonzero bandwidth sufficiently suppresses T_{cdw}.
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Affiliation(s)
- N C Costa
- Instituto de Física, Universidade Federal do Rio de Janeiro, Cx.P. 68.528, 21941-972 Rio de Janeiro RJ, Brazil
- Department of Physics, University of California, Davis, California 95616, USA
| | - T Blommel
- Department of Physics, University of California, Davis, California 95616, USA
- Department of Physics, North Dakota State University, Fargo, North Dakota 58105, USA
| | - W-T Chiu
- Department of Physics, University of California, Davis, California 95616, USA
| | - G Batrouni
- Université Côte d'Azur, INPHYNI, CNRS, 0600 Nice, France
- Beijing Computational Science Research Center, Beijing 100193, China
| | - R T Scalettar
- Department of Physics, University of California, Davis, California 95616, USA
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8
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Abstract
Based on first-principles molecular dynamics simulations at finite temperatures, we systematically study the adsorption and dissociation of water molecules on the γ-U(1 0 0) surface. We predict that water molecules spontaneously dissociate upon approaching the native γ-U(1 0 0) surface. The dissociation results from electronic interactions between surface uranium 6d states and 1b2, 3a1, and 1b1 molecular orbitals of water. With segregated Nb atoms existing on the surface, adsorbing water molecules also dissociate spontaneously because Nb 3d electronic states can also interact with the molecular orbitals similarly. After dissociation, the isolated hydrogen atoms are found to diffuse fast on both the γ-U surface and that with a surface substitutional Nb atom, which is very similar to the 'Hot-Atom' dissociation of oxygen molecules on the Al(1 1 1) surface. From a series of consecutive molecular dynamics simulations, we further reveal that on both the γ-U surface and that with a surface substitutional Nb atom, one surface U atom will be pulled out to form the U-O-U structure after dissociative adsorption of 0.44 ML water molecules. This result indicates that oxide nucleus can form at low coverage of water adsorption on the two surfaces.
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Affiliation(s)
- Yu Yang
- Institute of Applied Physics and Computational Mathematics, PO Box 8009, Beijing 100088, People's Republic of China
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9
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Lee S, Leighton C, Bates FS. Sphericity and symmetry breaking in the formation of Frank-Kasper phases from one component materials. Proc Natl Acad Sci U S A 2014; 111:17723-31. [PMID: 25378703 PMCID: PMC4273414 DOI: 10.1073/pnas.1408678111] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Frank-Kasper phases are tetrahedrally packed structures occurring in numerous materials, from elements to intermetallics to self-assembled soft materials. They exhibit complex manifolds of Wigner-Seitz cells with many-faceted polyhedra, forming an important bridge between the simple close-packed periodic and quasiperiodic crystals. The recent discovery of the Frank-Kasper σ-phase in diblock and tetrablock polymers stimulated the experiments reported here on a poly(isoprene-b-lactide) diblock copolymer melt. Analysis of small-angle X-ray scattering and mechanical spectroscopy exposes an undiscovered competition between the tendency to form self-assembled particles with spherical symmetry, and the necessity to fill space at uniform density within the framework imposed by the lattice. We thus deduce surprising analogies between the symmetry breaking at the body-centered cubic phase to σ-phase transition in diblock copolymers, mediated by exchange of mass, and the symmetry breaking in certain metals and alloys (such as the elements Mn and U), mediated by exchange of charge. Similar connections are made between the role of sphericity in real space for polymer systems, and the role of sphericity in reciprocal space for metallic systems such as intermetallic compounds and alloys. These findings establish new links between disparate materials classes, provide opportunities to improve the understanding of complex crystallization by building on synergies between hard and soft matter, and, perhaps most significantly, challenge the view that the symmetry breaking required to form reduced symmetry structures (possibly even quasiperiodic crystals) requires particles with multiple predetermined shapes and/or sizes.
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Affiliation(s)
- Sangwoo Lee
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180; and Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
| | - Chris Leighton
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
| | - Frank S Bates
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
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10
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Yoshida M, Ishii K, Jarrige I, Watanuki T, Kudo K, Koike Y, Kumagai K, Hiraoka N, Ishii H, Tsuei KD, Mizuki J. Momentum-resolved resonant inelastic X-ray scattering on a single crystal under high pressure. J Synchrotron Radiat 2014; 21:131-135. [PMID: 24365927 DOI: 10.1107/s1600577513028944] [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] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 10/21/2013] [Indexed: 06/03/2023]
Abstract
A single-crystal momentum-resolved resonant inelastic X-ray scattering (RIXS) experiment under high pressure using an originally designed diamond anvil cell (DAC) is reported. The diamond-in/diamond-out geometry was adopted with both the incident and scattered beams passing through a 1 mm-thick diamond. This enabled us to cover wide momentum space keeping the scattering angle condition near 90°. Elastic and inelastic scattering from the diamond was drastically reduced using a pinhole placed after the DAC. Measurement of the momentum-resolved RIXS spectra of Sr2.5Ca11.5Cu24O41 at the Cu K-edge was thus successful. Though the inelastic intensity becomes weaker by two orders than the ambient pressure, RIXS spectra both at the center and the edge of the Brillouin zone were obtained at 3 GPa and low-energy electronic excitations of the cuprate were found to change with pressure.
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Affiliation(s)
- Masahiro Yoshida
- Department of Physics, Tohoku University, Sendai 980-8578, Japan
| | - Kenji Ishii
- SPring-8, Japan Atomic Energy Agency, Sayo, Hyogo 679-5148, Japan
| | - Ignace Jarrige
- SPring-8, Japan Atomic Energy Agency, Sayo, Hyogo 679-5148, Japan
| | - Tetsu Watanuki
- SPring-8, Japan Atomic Energy Agency, Sayo, Hyogo 679-5148, Japan
| | - Kazutaka Kudo
- Department of Physics, Okayama University, Okayama 700-8530, Japan
| | - Yoji Koike
- Department of Applied Physics, Tohoku University, Sendai 980-8579, Japan
| | - Ken'ichi Kumagai
- Department of Physics, Hokkaido University, Sapporo 060-0810, Japan
| | - Nozomu Hiraoka
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Hirofumi Ishii
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Ku-Ding Tsuei
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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11
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Klintberg LE, Goh SK, Alireza PL, Saines PJ, Tompsett DA, Logg PW, Yang J, Chen B, Yoshimura K, Grosche FM. Pressure- and composition-induced structural quantum phase transition in the cubic superconductor (Sr, Ca)3Ir4Sn13. Phys Rev Lett 2012; 109:237008. [PMID: 23368250 DOI: 10.1103/physrevlett.109.237008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Indexed: 06/01/2023]
Abstract
We show that the quasi-skutterudite superconductor Sr(3)Ir(4)Sn(13) undergoes a structural transition from a simple cubic parent structure, the I phase, to a superlattice variant, the I' phase, which has a lattice parameter twice that of the high temperature phase. We argue that the superlattice distortion is associated with a charge density wave transition of the conduction electron system and demonstrate that the superlattice transition temperature T(*) can be suppressed to zero by combining chemical and physical pressure. This enables the first comprehensive investigation of a superlattice quantum phase transition and its interplay with superconductivity in a cubic charge density wave system.
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Affiliation(s)
- Lina E Klintberg
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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12
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He H, Wang P, Allred DD, Majewski J, Wilkerson MP, Rector KD. Characterization of Chemical Speciation in Ultrathin Uranium Oxide Layered Films. Anal Chem 2012; 84:10380-7. [DOI: 10.1021/ac302598r] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
| | | | - D. D. Allred
- Department of Physics
and Astronomy, Brigham Young University, Provo, Utah 84602, United
States
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Loa I, Isaev EI, McMahon MI, Kim DY, Johansson B, Bosak A, Krisch M. Lattice dynamics and superconductivity in cerium at high pressure. Phys Rev Lett 2012; 108:045502. [PMID: 22400861 DOI: 10.1103/physrevlett.108.045502] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 12/01/2011] [Indexed: 05/31/2023]
Abstract
We have measured phonon dispersion relations of the high-pressure phase cerium-oC4 (α' phase with the α-uranium crystal structure) at 6.5 GPa by using inelastic x-ray scattering. Pronounced phonon anomalies are observed, which are remarkably similar to those of α-U. First-principles electronic structure calculations reproduce the anomalies and allow us to identify strong electron-phonon coupling as their origin. At the low-pressure end of its stability range, Ce-oC4 is on the verge of a lattice-dynamical instability and possibly a charge density wave. The superconducting transition temperatures of the fcc, oC4, and mC4 phases of Ce have been calculated, and the superconductivity observed experimentally by Wittig and Probst is attributed to the oC4 phase.
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Affiliation(s)
- I Loa
- SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Edinburgh, United Kingdom.
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14
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Ekino T, Gabovich AM, Li MS, Pękała M, Szymczak H, Voitenko AI. d-Wave Superconductivity and s-Wave Charge Density Waves: Coexistence between Order Parameters of Different Origin and Symmetry. Symmetry (Basel) 2011; 3:699-749. [DOI: 10.3390/sym3040699] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A review of the theory describing the coexistence between d-wave superconductivity and s-wave charge-density-waves (CDWs) is presented. The CDW gapping is identified with pseudogapping observed in high-Tc oxides. According to the cuprate specificity, the analysis is carried out for the two-dimensional geometry of the Fermi surface (FS). Phase diagrams on the σ0 − α plane—here, σ0 is the ratio between the energy gaps in the parent pure CDW and superconducting states, and the quantity 2α is connected with the degree of dielectric (CDW) FS gapping—were obtained for various possible configurations of the order parameters in the momentum space. Relevant tunnel and photoemission experimental data for high-Tc oxides are compared with theoretical predictions. A brief review of the results obtained earlier for the coexistence between s-wave superconductivity and CDWs is also given.
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