We have studied the magnetization of the recently discovered heavy fermion superconductor UTe2 up to 56 T in pulsed-magnetic fields. A first-order metamagnetic transition has been clearly observed at Hm =34.9 T when the magnetic field H is applied along the orthorhombic hard-magnetization b-axis. The transition has a critical end point at ∼11 K and 34.8 T, where the first order transition terminates and changes into a crossover regime. Using the thermodynamic Maxwell relation, we have evaluated the field dependence of the Sommerfeld coefficient of the specific heat directly related to the superconducting pairing. From the analysis, we found a significant enhancement of the effective mass centered at Hm, which is reminiscent of the field-reentrant superconductivity of the ferromagnet URhGe in transverse fields. We discuss the origin of their field-robust superconductivity.
@article{arxiv.1905.02998,
title = {Metamagnetic Transition in Heavy Fermion Superconductor UTe2},
author = {Atsushi Miyake and Yusei Shimizu and Yoshiki J. Sato and DeXin Li and Ai Nakamura and Yoshiya Homma and Fuminori Honda and Jacques Flouquet and Masashi Tokunaga and Dai Aoki},
journal= {arXiv preprint arXiv:1905.02998},
year = {2019}
}
Comments
5 pages, 5 figures, accepted for publication in J. Phys. Soc. Jpn