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Yang J, Luo J, Yi C, Shi Y, Zhou Y, Zheng GQ. Spin-triplet superconductivity in K 2Cr 3As 3. SCIENCE ADVANCES 2021; 7:eabl4432. [PMID: 34936458 PMCID: PMC8694604 DOI: 10.1126/sciadv.abl4432] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 11/03/2021] [Indexed: 05/22/2023]
Abstract
A spin-triplet superconductor can harbor Majorana bound states that can be used in topological quantum computing. Recently, K2Cr3As3 and its variants with critical temperature Tc as high as 8 kelvin have emerged as a new class of superconductors with ferromagnetic spin fluctuations. Here, we report a discovery in K2Cr3As3 single crystal that the spin susceptibility measured by 75As Knight shift below Tc is unchanged with the magnetic field H0 applied in the ab plane but vanishes toward zero temperature when H0 is along the c axis, which unambiguously establishes this compound as a spin-triplet superconductor described by a vector order parameter d→ parallel to the c axis. Combining with point nodal gap, we show that K2Cr3As3 is a new platform for the study of topological superconductivity and its possible technical application.
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Affiliation(s)
- Jie Yang
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - Jun Luo
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - Changjiang Yi
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - Youguo Shi
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - Yi Zhou
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
- Kavli Institute for Theoretical Sciences, CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Guo-qing Zheng
- Department of Physics, Okayama University, Okayama 700-8530, Japan
- Corresponding author.
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2
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Saraiva TT, Baturina LI, Shanenko AA. Robust Superconductivity in Quasi-one-dimensional Multiband Materials. J Phys Chem Lett 2021; 12:11604-11608. [PMID: 34812633 DOI: 10.1021/acs.jpclett.1c03511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Recently it has been demonstrated that the pair-exchange coupling of quasi-one-dimensional (Q1D) bands with conventional higher-dimensional bands in one multiband superconducting material can result in the formation of a robust aggregate pair condensate. In particular, it has been found that the Q1D thermal pair fluctuations are suppressed in the presence of deep conventional band(s), for which the Fermi level is much larger than the characteristic cutoff energy. Here we report that the impact of the Q1D fluctuations is significantly weakened even in the presence of nearly shallow higher-dimensional band(s), which shed new light on the robust superconducting state observed in emerging chain-like-structured superconducting materials A2Cr3As3 (A = K, Rb, Cs).
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Affiliation(s)
| | - L I Baturina
- RTU MIREA, Lomonosov Institute of Fine Chemical Technologies, 119454, Moscow, Russia
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3
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Zhang L, Li J, Mu Q, Liu T, Yang D, Zhu C, Ren ZA, Tian H, Li ZA, Li J, Yang H. Microstructure of quasi-one-dimensional superconductor KCr 3As 3prepared by K-ion deintercalation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:215404. [PMID: 33588386 DOI: 10.1088/1361-648x/abe64d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
The microstructure of quasi-one-dimensional KCr3As3(133) superconductors, which were prepared by chemical cation deintercalation from their counterpart K2Cr3As3(233) compounds, are investigated using scanning transmission electron microscopy. The nominal KCr3As3crystals generally exhibit irregular nanoscale 133-phase domains accompanied by an amorphous As-deficient phase and cracks as a result of alkali cation deintercalation processes. Analysis of local defective structures reveals the existence of an intermediate state in the transformation from 233 to 133 phase and a possible K-deficient 233-type structure as a nanoscale cluster. Our microscopic investigations offer insight into the microstructure of KCr3As3and the alkali metal cation deintercalation processes.
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Affiliation(s)
- Lu Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Science, Beijing, 100190, People's Republic of China
| | - Jun Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
| | - Qingge Mu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Science, Beijing, 100190, People's Republic of China
| | - Tong Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Science, Beijing, 100190, People's Republic of China
| | - Dong Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, Shaanxi, 710119, People's Republic of China
| | - Chunhui Zhu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
| | - Zhi-An Ren
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Science, Beijing, 100190, People's Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, People's Republic of China
| | - Huanfang Tian
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
| | - Zi-An Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
| | - Jianqi Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Science, Beijing, 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, People's Republic of China
| | - Huaixin Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Science, Beijing, 100190, People's Republic of China
- Yangtze River Delta Physics Research Center Co., Ltd, Liyang, Jiangsu, 213300, People's Republic of China
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Saraiva TT, Cavalcanti PJF, Vagov A, Vasenko AS, Perali A, Dell'Anna L, Shanenko AA. Multiband Material with a Quasi-1D Band as a Robust High-Temperature Superconductor. PHYSICAL REVIEW LETTERS 2020; 125:217003. [PMID: 33275004 DOI: 10.1103/physrevlett.125.217003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/26/2020] [Accepted: 10/26/2020] [Indexed: 06/12/2023]
Abstract
It is well known that superconductivity in quasi-one-dimensional (Q1D) materials is hindered by large fluctuations of the order parameter. They reduce the critical temperature and can even destroy the superconductivity altogether. Here it is demonstrated that the situation changes dramatically when a Q1D pair condensate is coupled to a higher-dimensional stable one, as in recently discovered multiband Q1D superconductors. The fluctuations are suppressed even by vanishingly small pair-exchange coupling between different band condensates and the superconductor is well described by the mean field theory. In this case the low dimensionality effects enhance the coherence of the system instead of suppressing it. As a result, the critical temperature of the multiband Q1D superconductor can increase by orders of magnitude when the system is tuned to the Lifshitz transition with the Fermi level close to the edge of the Q1D band.
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Affiliation(s)
- T T Saraiva
- National Research University Higher School of Economics, 101000 Moscow, Russia
| | - P J F Cavalcanti
- Departamento de Fsica, Universidade Federal de Pernambuco, Cidade Universitria, 50670-901 Recife-PE, Brazil
| | - A Vagov
- Institut für Theoretische Physik III, Bayreuth Universität, Bayreuth 95440, Germany
| | - A S Vasenko
- National Research University Higher School of Economics, 101000 Moscow, Russia
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, San Sebastián/Donostia, 20018 Basque Country, Spain
| | - A Perali
- School of Pharmacy, Physics Unit, University of Camerino, I-62032 Camerino, Italy
| | - L Dell'Anna
- Dipartimento di Fisica e Astronomia "Galileo Galilei," Università di Padova, Via Marzolo 8, 35131 Padova, Italy
| | - A A Shanenko
- National Research University Higher School of Economics, 101000 Moscow, Russia
- Departamento de Fisica, Universidade Federal de Pernambuco, Cidade Universitaria, 50670-901 Recife-PE, Brazil
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5
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Jiao WH, Huang YN, Xu XF, Li YK, Liu Y, Wang ZC, Xu XL, Feng YX, Feng CM, Cao GH. Normal-state properties of the quasi-one-dimensional superconductor Ta 4Pd 3Te 16. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:325601. [PMID: 31042685 DOI: 10.1088/1361-648x/ab1e9c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We examined the physical properties of the quasi-one-dimensional superconductor Ta4Pd3Te16 in the normal state by detailed measurements of susceptibility, in-plane anisotropic resistivity, magnetoresistance, Hall resistivity, and Seebeck coefficient. The large Wilson ratio, as inferred from normal-state susceptibility, indicates strong electron-electron interaction. The Hall and Seebeck coefficients show not only significant temperature-dependent behavior, indicating the multiband effect, but also an obvious anomaly around T 1 = 40 K. Analyses of both the Hall resistivity and thermopower using a two-band model indicate that the electrons dominate the electrical transport at low temperatures. Our results imply that it is the quantum fluctuations of the charge order taking place in the temperature range 30-50 K that may result in the abnormal normal-state properties of Ta4Pd3Te16.
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Affiliation(s)
- Wen-He Jiao
- Department of Physics, Zhejiang University of Science and Technology, Hangzhou 310023, People's Republic of China
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6
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Luo J, Yang J, Zhou R, Mu QG, Liu T, Ren ZA, Yi CJ, Shi YG, Zheng GQ. Tuning the Distance to a Possible Ferromagnetic Quantum Critical Point in A_{2}Cr_{3}As_{3}. PHYSICAL REVIEW LETTERS 2019; 123:047001. [PMID: 31491262 DOI: 10.1103/physrevlett.123.047001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Indexed: 06/10/2023]
Abstract
Although superconductivity in the vicinity of an antiferromagnetic (AFM) instability has been extensively explored in the last three decades or so, superconductivity in compounds with a background of ferromagnetic (FM) spin fluctuations is still rare. We report ^{75}As nuclear quadrupole resonance measurements on the A_{2}Cr_{3}As_{3} family, which is the first group of Cr-based superconductors at ambient pressure, with A being alkali elements. From the temperature dependence of the spin-lattice relaxation rate (1/T_{1}), we find that by changing A in the order of A=Na, Na_{0.75}K_{0.25}, K, and Rb, the system is tuned to approach a possible FM quantum critical point (QCP). This may be ascribed to the Cr2-As2-Cr2 bond angle that decreases towards 90°, which enhances the FM interaction via the Cr2-As2-Cr2 path. Upon moving away from the QCP, the superconducting transition temperature T_{sc} increases progressively up to 8.0 K in Na_{2}Cr_{3}As_{3}, which is in sharp contrast to the AFM case where T_{sc} usually shows a maximum around a QCP. The 1/T_{1} decreases rapidly below T_{sc} with no Hebel-Slichter peak, and ubiquitously follows a T^{5} variation below a characteristic temperature T^{*}≈0.6 T_{sc}, which indicates the existence of point nodes in the superconducting gap function commonly in the family. These results suggest that the A_{2}Cr_{3}As_{3} family is a possible solid-state analog of superfluid ^{3}He.
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Affiliation(s)
- J Luo
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - J Yang
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - R Zhou
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - Q G Mu
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - T Liu
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zhi-An Ren
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - C J Yi
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Y G Shi
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
| | - Guo-Qing Zheng
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing 100190, China
- Department of Physics, Okayama University, Okayama 700-8530, Japan
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7
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Mu QG, Ruan BB, Pan BJ, Liu T, Zhao K, Chen GF, Ren ZA. Na-doping effects on structural evolution and superconductivity in (K 1-x Na x ) 2Cr 3As 3 (x = 0-1). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:225701. [PMID: 30818283 DOI: 10.1088/1361-648x/ab0b94] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this report, we studied the effects of isovalent Na-doping on the recently discovered quasi-one-dimensional Cr-based unconventional superconductor K2Cr3As3. A series of polycrystalline samples with nominal component (K1-x Na x )2Cr3As3 (x = 0-1) were synthesized by the solid state reaction method. From crystal structure and chemical phase characterizations, we found two distinct chemical phases with the same hexagonal structure but distinguished by different site occupancy of Na+ ions at the two kinds of K-site in the K2Cr3As3 lattice structure. When x ⩽ 0.4, the doped samples form a continuous sosoloid phase of (K1-x Na x )2Cr3As3 with the Na+ ions randomly doping at the K-sites (denoted as α-phase); when x ⩾ 0.5, a novel individual phase of (K0.25Na0.75)2Cr3As3 emerges, in which the Na+ ions selectively occupy all the '3k' sites and the K+ ions occupy the '1c' sites (denoted as β-phase). No chemical phase of Na2Cr3As3 was detected. Superconductivity in these samples was studied by electrical transport and magnetic susceptibility measurements, and it evolves in a much sophisticated manner. In the α-phase, the superconducting T c decreases quickly upon Na-doping. All these α-phase samples have surprisingly low superconducting volume fraction and relatively low T c compared with the undoped K2Cr3As3. However, the β-phase has a clearly enhanced T c up to 7.6 K which locates between the values of K2Cr3As3 and Na2Cr3As3, and exhibits a full superconducting shielding signal.
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Affiliation(s)
- Qing-Ge Mu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China. School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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8
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Reja S, Nishimoto S. Triplet superconductivity in coupled odd-gon rings. Sci Rep 2019; 9:2691. [PMID: 30804416 PMCID: PMC6389994 DOI: 10.1038/s41598-019-39130-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 01/10/2019] [Indexed: 11/09/2022] Open
Abstract
Shedding light on the nature of spin-triplet superconductivity has been a long-standing quest in condensed matter physics since the discovery of superfluidity in liquid 3He. Nevertheless, the mechanism of spin-triplet pairing is much less understood than that of spin-singlet pairing explained by the Bardeen-Cooper-Schrieffer theory or even observed in high-temperature superconductors. Here we propose a versatile mechanism for spin-triplet superconductivity which emerges through a melting of macroscopic spin polarization stabilized in weakly coupled odd-gon (e.g., triangle, pentagon, etc) systems. We demonstrate the feasibility of sustaining spin-triplet superconductivity with this mechanism by considering a new class of quasi-one-dimensional superconductors A2Cr3As3 (A = K, Rb, and Cs). Furthermore, we suggest a simple effective model to easily illustrate the adaptability of the mechanism to general systems consisting of odd-gon units. This mechanism provides a rare example of superconductivity from on-site Coulomb repulsion.
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Affiliation(s)
- Sahinur Reja
- Department of Physics, Indiana University, Bloomington, Indiana, 47405, USA. .,School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland, 4072, Australia.
| | - Satoshi Nishimoto
- Department of Physics, Technical University Dresden, Dresden, 01069, Germany. .,Institute for Theoretical Solid State Physics, IFW Dresden, Dresden, 01069, Germany.
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Chen RY, Wang NL. Progress in Cr- and Mn-based superconductors: a key issues review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:012503. [PMID: 30523906 DOI: 10.1088/1361-6633/aaed0d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The presence of magnetic ions was first believed to be detrimental to superconductivity. However, unconventional superconductivity has been widely induced by doping or applying external pressure in magnetic systems such as heavy fermion, cuprate and iron-based superconductors in which magnetic fluctuations are suggested to serve as the pairing glue for Cooper pairs. The discovery of superconductivity in the magnetic compounds CrAs and MnP under high pressures has further expanded this family of superconductors and provided new platforms for investigating the interplay between magnetism and superconductivity. CrAs and MnP represent the first superconductors among the transition metal Cr- and Mn-based compounds in which the electronic states near the Fermi level are dominated by Cr/Mn 3d electrons. Shortly after their discovery, new types of Cr-based quasi-one-dimensional superconductors A2Cr3As3 and ACr3As3 (A [Formula: see text] K, Rb, Cs or Na) were discovered at ambient pressure. The close proximity of superconductivity to magnetic instability in these systems suggests that spin fluctuations may play crucial roles in mediating the Cooper pairing. In this article we review the basic physical properties of these novel superconductors and the progress achieved in recent studies.
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Affiliation(s)
- R Y Chen
- Center for Advanced Quantum Studies, Department of Physics, Beijing Normal University, Beijing 100875, People's Republic of China
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Taddei KM, Xing G, Sun J, Fu Y, Li Y, Zheng Q, Sefat AS, Singh DJ, de la Cruz C. Frustrated Structural Instability in Superconducting Quasi-One-Dimensional K_{2}Cr_{3}As_{3}. PHYSICAL REVIEW LETTERS 2018; 121:187002. [PMID: 30444378 DOI: 10.1103/physrevlett.121.187002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Indexed: 06/09/2023]
Abstract
We present density functional theory and neutron total scattering studies on quasi-one-dimensional superconducting K_{2}Cr_{3}As_{3} revealing a frustrated structural instability. Our first principles calculations find a significant phonon instability, which, under energy minimization, corresponds to a frustrated orthorhombic distortion. In neutron diffraction studies we find large atomic displacement parameters with anomalous temperature dependencies, which result from highly localized orthorhombic distortions of the CrAs sublattice and coupled K displacements. These results suggest a more complex phase diagram than previously assumed for K_{2}Cr_{3}As_{3} with subtle interplays of structure, electron-phonon, and magnetic interactions.
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Affiliation(s)
- Keith M Taddei
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Guangzong Xing
- Department of Physics and Astronomy, University of Missouri, Missouri 65211, USA
| | - Jifeng Sun
- Department of Physics and Astronomy, University of Missouri, Missouri 65211, USA
| | - Yuhao Fu
- Department of Physics and Astronomy, University of Missouri, Missouri 65211, USA
| | - Yuwei Li
- Department of Physics and Astronomy, University of Missouri, Missouri 65211, USA
| | - Qiang Zheng
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Athena S Sefat
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - David J Singh
- Department of Physics and Astronomy, University of Missouri, Missouri 65211, USA
| | - Clarina de la Cruz
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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11
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Mu QG, Ruan BB, Zhao K, Pan BJ, Liu T, Shan L, Chen GF, Ren ZA. Superconductivity at 10.4 K in a novel quasi-one-dimensional ternary molybdenum pnictide K 2Mo 3As 3. Sci Bull (Beijing) 2018; 63:952-956. [PMID: 36658890 DOI: 10.1016/j.scib.2018.06.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/13/2018] [Accepted: 06/14/2018] [Indexed: 01/21/2023]
Abstract
Here we report the discovery of the first ternary molybdenum pnictide based superconductor K2Mo3As3. Polycrystalline samples were synthesized by the conventional solid state reaction method. X-ray diffraction analysis reveals a quasi-one-dimensional hexagonal crystal structure with (Mo3As3)2- linear chains separated by K+ ions, similar as previously reported K2Cr3As3, with the space group of P-6m2 (No. 187) and the refined lattice parameters a = 10.145(5) Å and c = 4.453(8) Å. Electrical resistivity, magnetic susceptibility, and heat capacity measurements exhibit bulk superconductivity with the onset Tc at 10.4 K in K2Mo3As3 which is higher than the isostructural Cr-based superconductors. Being the same group VIB transition elements and with similar structural motifs, these Cr and Mo based superconductors may share some common underlying origins for the occurrence of superconductivity and need more investigations to uncover the electron pairing within a quasi-one-dimensional chain structure.
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Affiliation(s)
- Qing-Ge Mu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin-Bin Ruan
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kang Zhao
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bo-Jin Pan
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tong Liu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lei Shan
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
| | - Gen-Fu Chen
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
| | - Zhi-An Ren
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, China.
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12
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Sun JP, Jiao YY, Yang CL, Wu W, Yi CJ, Wang BS, Shi YG, Luo JL, Uwatoko Y, Cheng JG. Effect of hydrostatic pressure on the superconducting properties of quasi-1D superconductor K 2Cr 3As 3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:455603. [PMID: 29049031 DOI: 10.1088/1361-648x/aa8c94] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
K2Cr3As3 is a newly discovered quasi-1D superconductor with a T c = 6.1 K and an upper critical field µ 0 H c2(0) ≈ 40 T three times larger than the Pauli paramagnetic limit µ 0 H p that is suggestive of a spin-triplet Cooper pairing. In this paper, we have investigated the effects of hydrostatic pressure on its T c and µ 0 H c2 by measuring the ac magnetic susceptibility χ'(T) under magnetic fields at various hydrostatic pressures up to 7.5 GPa. The major findings include: (1) T c is suppressed gradually to below 2 K at 7.5 GPa; (2) the estimated µ 0 H c2(0) decreases dramatically to below µ 0 H p above ~2 GPa and becomes slight lower than the orbital limiting field [Formula: see text] estimated from the initial slope of upper critical field via [Formula: see text] = -0.73T cdH c2/[Formula: see text] in the clean limit; (3) the estimated Maki parameter α = √2[Formula: see text]/H p drops from 4 at ambient pressure to well below 1 at P > 2 GPa, suggesting the crossover from Pauli paramagnetic limiting to orbital limiting in the pair breaking process upon increasing pressure. These observations suggested that the application of hydrostatic pressure could drive K2Cr3As3 away from the ferromagnetic instability and lead to a breakdown of the spin-triplet pairing channel. We have also made a side-by-side comparison and discussed the distinct effects of chemical and physical pressures on the superconducting properties of K2Cr3As3.
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Affiliation(s)
- J P Sun
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China. School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
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13
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Tang ZT, Liu Y, Bao JK, Xi CY, Pi L, Cao GH. Anisotropic upper critical magnetic fields in Rb 2Cr 3As 3 superconductor. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:424002. [PMID: 28786820 DOI: 10.1088/1361-648x/aa84eb] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Rb2Cr3As3 is a structurally one-dimensional superconductor containing Cr3As3 chains with a superconducting transition temperature of [Formula: see text] K. Here we report the electrical resistance measurements for Rb2Cr3As3 single crystals, under magnetic fields up to 29.5 T and at temperatures down to 0.36 K, from which the upper critical fields, [Formula: see text], can be obtained in a broad temperature range. For field parallel to the Cr3As3 chains, [Formula: see text] is paramagnetically limited with an initial slope of [Formula: see text]d[Formula: see text]/d[Formula: see text] T [Formula: see text] and a zero-temperature upper critical field of [Formula: see text] T. For field perpendicular to the Cr3As3 chains, however, [Formula: see text] is only limited by orbital pair-breaking effect with [Formula: see text]d[Formula: see text]/d[Formula: see text] T [Formula: see text]. As a consequence, the anisotropy [Formula: see text] decreases sharply near T c and reverses below 2 K. Remarkably, the low-temperature [Formula: see text] down to 0.075 [Formula: see text] remains to increase linearly up to over three times the Pauli paramagnetic limit, which strongly suggests dominant spin-triplet superconductivity in Rb2Cr3As3.
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Affiliation(s)
- Zhang-Tu Tang
- Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China
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Watson MD, Feng Y, Nicholson CW, Monney C, Riley JM, Iwasawa H, Refson K, Sacksteder V, Adroja DT, Zhao J, Hoesch M. Multiband One-Dimensional Electronic Structure and Spectroscopic Signature of Tomonaga-Luttinger Liquid Behavior in K_{2}Cr_{3}As_{3}. PHYSICAL REVIEW LETTERS 2017; 118:097002. [PMID: 28306267 DOI: 10.1103/physrevlett.118.097002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Indexed: 06/06/2023]
Abstract
We present angle-resolved photoemission spectroscopy measurements of the quasi-one-dimensional superconductor K_{2}Cr_{3}As_{3}. We find that the Fermi surface contains two Fermi surface sheets, with linearly dispersing bands not displaying any significant band renormalizations. The one-dimensional band dispersions display a suppression of spectral intensity approaching the Fermi level according to a linear power law, over an energy range of ∼200 meV. This is interpreted as a signature of Tomonoga-Luttinger liquid physics, which provides a new perspective on the possibly unconventional superconductivity in this family of compounds.
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Affiliation(s)
- M D Watson
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
| | - Y Feng
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - C W Nicholson
- Department of Physical Chemistry, Fritz-Haber-Institut of the Max Planck Society, Faradayweg 4-6, Berlin 14915, Germany
| | - C Monney
- Department of Physics, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - J M Riley
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, United Kingdom
| | - H Iwasawa
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
| | - K Refson
- Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, United Kingdom
| | - V Sacksteder
- Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom
| | - D T Adroja
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, United Kingdom
- Highly Correlated Matter Research Group, Physics Department, University of Johannesburg, P.O. Box 524, Auckland Park 2006, South Africa
| | - J Zhao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - M Hoesch
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
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Smidman M, Salamon MB, Yuan HQ, Agterberg DF. Superconductivity and spin-orbit coupling in non-centrosymmetric materials: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2017; 80:036501. [PMID: 28072583 DOI: 10.1088/1361-6633/80/3/036501] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In non-centrosymmetric superconductors, where the crystal structure lacks a centre of inversion, parity is no longer a good quantum number and an electronic antisymmetric spin-orbit coupling (ASOC) is allowed to exist by symmetry. If this ASOC is sufficiently large, it has profound consequences on the superconducting state. For example, it generally leads to a superconducting pairing state which is a mixture of spin-singlet and spin-triplet components. The possibility of such novel pairing states, as well as the potential for observing a variety of unusual behaviors, led to intensive theoretical and experimental investigations. Here we review the experimental and theoretical results for superconducting systems lacking inversion symmetry. Firstly we give a conceptual overview of the key theoretical results. We then review the experimental properties of both strongly and weakly correlated bulk materials, as well as two dimensional systems. Here the focus is on evaluating the effects of ASOC on the superconducting properties and the extent to which there is evidence for singlet-triplet mixing. This is followed by a more detailed overview of theoretical aspects of non-centrosymmetric superconductivity. This includes the effects of the ASOC on the pairing symmetry and the superconducting magnetic response, magneto-electric effects, superconducting finite momentum pairing states, and the potential for non-centrosymmetric superconductors to display topological superconductivity.
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Affiliation(s)
- M Smidman
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, People's Republic of China
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16
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Zhou Y, Cao C, Zhang FC. Theory for superconductivity in alkali chromium arsenides A 2Cr 3As 3 (A=K, Rb, Cs). Sci Bull (Beijing) 2017; 62:208-211. [PMID: 36659407 DOI: 10.1016/j.scib.2017.01.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 12/26/2016] [Accepted: 12/26/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Yi Zhou
- Department of Physics, Zhejiang University, Hangzhou 310027, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China.
| | - Chao Cao
- Department of Physics, Hangzhou Normal University, Hangzhou 310036, China
| | - Fu-Chun Zhang
- Department of Physics, Zhejiang University, Hangzhou 310027, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
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17
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Wang Z, Yi W, Wu Q, Sidorov VA, Bao J, Tang Z, Guo J, Zhou Y, Zhang S, Li H, Shi Y, Wu X, Zhang L, Yang K, Li A, Cao G, Hu J, Sun L, Zhao Z. Correlation between superconductivity and bond angle of CrAs chain in non-centrosymmetric compounds A 2Cr 3As 3 (A = K, Rb). Sci Rep 2016; 6:37878. [PMID: 27886268 PMCID: PMC5122944 DOI: 10.1038/srep37878] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 11/02/2016] [Indexed: 11/22/2022] Open
Abstract
Non-centrosymmetric superconductors, whose crystal structure is absent of inversion symmetry, have recently received special attentions due to the expectation of unconventional pairings and exotic physics associated with such pairings. The newly discovered superconductors A2Cr3As3 (A = K, Rb), featured by the quasi-one dimensional structure with conducting CrAs chains, belongs to such kind of superconductor. In this study, we are the first to report the finding that superconductivity of A2Cr3As3 (A = K, Rb) has a positive correlation with the extent of non-centrosymmetry. Our in-situ high pressure ac susceptibility and synchrotron x-ray diffraction measurements reveal that the larger bond angle of As-Cr-As (defined as α) in the CrAs chains can be taken as a key factor controlling superconductivity. While the smaller bond angle (defined as β) and the distance between the CrAs chains also affect the superconductivity due to their structural connections with the α angle. We find that the larger value of α-β, which is associated with the extent of the non-centrosymmetry of the lattice structure, is in favor of superconductivity. These results are expected to shed a new light on the underlying mechanism of the superconductivity in these Q1D superconductors and also to provide new perspective in understanding other non-centrosymmetric superconductors.
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Affiliation(s)
- Zhe Wang
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei Yi
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Qi Wu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Vladimir A. Sidorov
- Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Moscow, Russia
| | - Jinke Bao
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Zhangtu Tang
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Jing Guo
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Yazhou Zhou
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Shan Zhang
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hang Li
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Youguo Shi
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Xianxin Wu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Ling Zhang
- Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China
| | - Ke Yang
- Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China
| | - Aiguo Li
- Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China
| | - Guanghan Cao
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Jiangping Hu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100190, China
| | - Liling Sun
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100190, China
| | - Zhongxian Zhao
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100190, China
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Zhong H, Feng XY, Chen H, Dai J. Formation of Molecular-Orbital Bands in a Twisted Hubbard Tube: Implications for Unconventional Superconductivity in K_{2}Cr_{3}As_{3}. PHYSICAL REVIEW LETTERS 2015; 115:227001. [PMID: 26650315 DOI: 10.1103/physrevlett.115.227001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Indexed: 06/05/2023]
Abstract
We study a twisted Hubbard tube modeling the [CrAs]_{∞} structure of quasi-one-dimensional superconductors A_{2}Cr_{3}As_{3} (A=K, Rb, Cs). The molecular-orbital bands emerging from the quasi-degenerate atomic orbitals are exactly solved. An effective Hamiltonian is derived for a region where three partially filled bands intersect the Fermi energy. The deduced local interactions among these active bands show a significant reduction compared to the original atomic interactions. The resulting three-channel Luttinger liquid shows various interaction-induced instabilities including two kinds of spin-triplet superconducting instabilities due to gapless spin excitations, with one of them being superseded by the spin-density-wave phase in the intermediate Hund's coupling regime. The implications of these results for the alkali chromium arsenides are discussed.
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Affiliation(s)
- Hanting Zhong
- Condensed Matter Group, Department of Physics, Hangzhou Normal University, Hangzhou 310036, China
| | - Xiao-Yong Feng
- Condensed Matter Group, Department of Physics, Hangzhou Normal University, Hangzhou 310036, China
- Hangzhou Key Laboratory of Quantum Matter, Hangzhou Normal University, Hangzhou 310036, China
| | - Hua Chen
- International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Jianhui Dai
- Condensed Matter Group, Department of Physics, Hangzhou Normal University, Hangzhou 310036, China
- Hangzhou Key Laboratory of Quantum Matter, Hangzhou Normal University, Hangzhou 310036, China
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Yang J, Tang ZT, Cao GH, Zheng GQ. Ferromagnetic Spin Fluctuation and Unconventional Superconductivity in Rb2Cr3As3 Revealed by 75As NMR and NQR. PHYSICAL REVIEW LETTERS 2015; 115:147002. [PMID: 26551818 DOI: 10.1103/physrevlett.115.147002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Indexed: 06/05/2023]
Abstract
We report (75)As nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) studies on the superconductor Rb(2)Cr(3)As(3) with a quasi-one-dimensional crystal structure. Below T∼100 K, the spin-lattice relaxation rate (1/T(1)) divided by temperature, 1/T(1)T, increases upon cooling down to T(c)=4.8 K, showing a Curie-Weiss-like temperature dependence. The Knight shift also increases with decreasing temperature. These results suggest ferromagnetic spin fluctuation. In the superconducting state, 1/T(1) decreases rapidly below T(c) without a Hebel-Slichter peak, and follows a T(5) variation below T∼3 K, which points to unconventional superconductivity with point nodes in the gap function.
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Affiliation(s)
- J Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Z T Tang
- Department of Physics and State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310027, China
| | - G H Cao
- Department of Physics and State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310027, China
- Collaborative Innovation Centre of Advanced Microstructures, Nanjing 210093, China
| | - Guo-Qing Zheng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Department of Physics, Okayama University, Okayama 700-8530, Japan
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Alemany P, Canadell E. Links between the Crystal and Electronic Structure in the New Family of Unconventional Superconductors A2Cr3As3 (A = K, Rb, Cs). Inorg Chem 2015; 54:8029-34. [PMID: 26230077 DOI: 10.1021/acs.inorgchem.5b01207] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The electronic structure of a new family of superconductors is examined through density functional theory calculations. In contrast with other quasi-1D superconductors, these phases exhibit a relatively complex electronic structure and the Fermi surface contains both 1D and 3D components. It is shown that cations have an almost nil influence on the electronic structure. The absence of a structural Peierls modulation is discussed, and the differences with the structurally related M2Mo6Se6 (M = Tl, In, ...) superconductors are stressed. The large electron mass renormalization and the lack of clear correlation between N(EF) and Tc suggest the existence of strong electron correlations and an unconventional origin of the superconductivity.
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Affiliation(s)
- Pere Alemany
- †Departament de Química Física and Institut de Química Teórica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Enric Canadell
- ‡Institut de Ciència de Materials de Barcelona (CSIC), Campus de la UAB, 08193 Bellaterra, Spain
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