Spin fluctuations driving field-reinforced superconductivity in UTe

UTeの磁場強化型超伝導を誘起するスピン揺らぎ

徳永 陽  

Tokunaga, Yo

Te NMR measurements reveal an enhancement of electronic spin fluctuations above 15 T, leading to their divergence in the vicinity of the metamagnetic transition at 35 T, below which field-reinforced superconductivity appears when a magnetic field is applied along the crystallographic axis. The NMR data evidence that these fluctuations are dominantly longitudinal, providing a key to understanding the peculiar superconducting phase diagram in H//b, where such fluctuations enhance the pairing interactions.