The screening response of vortices in kagome superconductor CsV3Sb5 was measured using the ac mutual inductance technique. Besides confirming the absence of gapless quasiparticles in zero external magnetic field, we observe the peak effect, manifested in enhanced vortex pinning strength and critical current, in a broad intermediate range of magnetic field. The peaks are followed by another crossover from strong to weak pinning, unlike the usual peak effect that diminishes smoothly at Hc2. Hysteresis in the screening response allows the identification of a vortex glass phase which strongly correlates with the onset of the peaks. A variety of features in the temperature- and field-dependence of the screening response, corroborated by resistance and dc magnetization measurements, have allowed us to extract an H-T phase diagram of the vortex states and to infer the irreversibility line Hirr(T).
@article{arxiv.2306.13297,
title = {Vortex phase diagram of kagome superconductor CsV$_3$Sb$_5$},
author = {Xinyang Zhang and Mark Zic and Dong Chen and Chandra Shekhar and Claudia Felser and Ian R. Fisher and Aharon Kapitulnik},
journal= {arXiv preprint arXiv:2306.13297},
year = {2024}
}