Year: 2025
Type: article
Abstract: On the kagome lattice, electrons benefit from the simultaneous presence of band topology, flat electronic bands, and Van Hove singularities, forming competing or cooperating orders. Understanding the interrelation between these distinct order parameters remains a significant challenge, leaving much of the associated physics unexplored. In the kagome superconductor KV_{3}Sb_{5}, which exhibits a charge density wave (CDW) state below T≃78 K, we uncover an unpredicted field-induced phase transition below 6 K. The observed transition is marked by a hysteretic anomaly in the resistivity, nonlinear electrical transport, and a change in the symmetry of the electronic response as probed via the angular dependence of the magnetoresistivity. These observations surprisingly suggest the emergence of an unanticipated broken symmetry state coexisting with the original CDW. To understand this experimental observation, we developed a theoretical minimal model for the normal state inside the high-temperature parent CDW phase, where an incommensurate CDW order emerges as an instability subleading to superconductivity. The incommensurate CDW emerges when superconducting fluctuations become fully suppressed by large magnetic fields. Our results suggest that, in kagome superconductors, quantum states can either coexist or are nearly degenerate in energy, indicating that these are rich platforms to expose new correlated phenomena.
Source: Physical Review Letters
DOI: 10.1103/5f9f-bsqw
Authors: Md. Shafayat Hossain, Qi Zhang, Julian Ingham, Jinjin Liu, Sen Shao, Yangmu Li, Yuxin Wang, Bal K. Pokharel, Zi-Jia Cheng, Yu-Xiao Jiang, Maksim Litskevich, Byunghoon Kim, Xian Yang, Yongkai Li, Tyler A. Cochran, Yugui Yao, Dragana Popović, Zhiwei Wang, Ronny Thomale, Luis Balicas, M. Zahid Hasan
Institutions: California NanoSystems Institute, University of California, Los Angeles, Princeton University, Columbia University, Beijing Institute of Technology, Nanyang Technological University, Chinese Academy of Sciences, Institute of Physics, National High Magnetic Field Laboratory, University of Würzburg
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, U.S. Department of Energy, Gordon and Betty Moore Foundation, Princeton University, National High Magnetic Field Laboratory, National Natural Science Foundation of China, Beijing Institute of Technology, Office of Science, Beijing Municipal Natural Science Foundation, National Key Research and Development Program of China, Division of Materials Research, Basic Energy Sciences, High Magnetic Field Laboratory, Chinese Academy of Sciences, Oak Ridge National Laboratory
Awards: G1019936685, G1422473640, G1521609874, SYNCHOTRON X-RAY BASED ELECTRONIC STRUCTURE STUDY OF CORRELATED QUANTUM MATERIALS, G3031809386, G3492921395, G3550235517, G358655052, G3592830065, G3884879969, G4092704135, G507888039, G6656473614, National High Magnetic Field Laboratory Renewal 2023-2027, G742574937, G7440376127, G7637316338, G8152425740, G8346949607, Charge Fluctuations and Competing Orders in Strongly Correlated Materials, NEW: SISGR - HIGH MAGNETIC FIELDS AS A PROBE TO UNVEIL THE PHYSICAL PROPERTIES OF THE NEWLY DISCOVERED FE OXYPNICTIDE SUPERCONDUCTORS AND RELATED COM, G8618556185, M. Zahid Hasan Experimental Investigator Award, G9000170913
OpenAlex ID: W4415667445