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arXiv · 2408.06178

Time-reversal symmetry-breaking phenomena in transport study of kagome superconductivity

Shuo-Ying Yang·Jia-Xin Yin
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Abstract

Recent studies have found that all three materials within the vanadium-based kagome superconductors ($\textit{A}$V$_{3}$Sb$_{5}$, $\textit{A}$ = K, Cs, Rb) exhibit time-reversal symmetry-breaking behaviors in the superconducting states. Among the three, the Josephson junctions structured Nb/K$_{1-x}$V$_{3}$Sb$_{5}$/Nb and RbV$_{3}$Sb$_{5}$ show magnetic hysteresis below the superconducting transition temperature. CsV$_{3}$Sb$_{5}$ exhibits a zero-field superconducting diode effect, meaning the magnitude of the positive and negative superconducting critical currents are different. We first discuss the similarities and differences among the three above-mentioned experiments. Then, we discuss the possible mechanisms responsible for the unconventional superconducting transport phenomena: such as a chiral superconducting order parameter, and chiral pair density waves arising from the intertwining of the chiral charge order with superconductivity.

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Shuo-Ying Yang, Jia-Xin Yin. 2024-08-12. Time-reversal symmetry-breaking phenomena in transport study of kagome superconductivity. https://doi.org/10.7498/aps.73.20240917

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