Self-reconstruction of order parameter in spin-triplet superconductor UTe$_2$

Y. Tokiwa; P. Opletal; H. Sakai; K. Kubo; S. Kambe; E. Yamamoto; M. Kimata; S. Awaji; T. Sasaki; D. Aoki; Y. Yanase; Y. Tokunaga; Y. Haga

doi:10.1103/z8yx-yzdh

arXiv · 2210.11769

Self-reconstruction of order parameter in spin-triplet superconductor UTe$_2$

Y. Tokiwa·P. Opletal·H. Sakai·K. Kubo·S. Kambe·E. Yamamoto·M. Kimata·S. Awaji·T. Sasaki·D. Aoki·Y. Yanase·Y. Tokunaga·Y. Haga

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Abstract

We investigate the effect of easy-axis metamagnetic crossover on superconductivity in UTe$_2$ along the $a$-axis through measurements of AC susceptibility, magnetization, and the magnetocaloric effect. In ultra-clean single crystals, we identify a field-induced phase transition within the superconducting state at 5.6 T, driven by metamagnetism. This transition leads to a high-field superconducting state, significantly increasing the upper critical field to 12 T. A sudden increase in entropy at the transition suggests a self-reconstruction of the order parameter, enabling multi-component superconducting states to adapt to external perturbations.

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Y. Tokiwa, P. Opletal, H. Sakai, K. Kubo, S. Kambe, E. Yamamoto, M. Kimata, S. Awaji, T. Sasaki, D. Aoki, Y. Yanase, Y. Tokunaga, Y. Haga. 2022-10-21. Self-reconstruction of order parameter in spin-triplet superconductor UTe$_2$. https://doi.org/10.1103/z8yx-yzdh

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