Magnetoresistance hysteresis in the superconducting state of kagome CsV₃Sb₅

The hysteresis of magnetoresistance observed in superconductors is of great interest due to its potential connection with unconventional superconductivity. In this study, we perform electrical transport measurements on kagome superconductor CsV₃Sb₅ nanoflakes and uncover unusual hysteretic behavior of magnetoresistance in the superconducting state. This hysteresis can be induced by applying either a large DC or AC current at temperatures (T) well below the superconducting transition temperature (T_c). As T approaches T_c, similar weak hysteresis is also detected by applying a small current. Various scenarios are discussed, with particular focus on the effects of vortex pinning and the presence of time-reversal-symmtery-breaking superconducting domains. Our findings support the latter, hinting at chiral superconductivity in kagome superconductors.