Intrinsic Anomalous Thermal Hall Effect in the Unconventional Superconductor UTe2

Abstract

We investigate the intrinsic anomalous thermal Hall effect as an effective probe of the order parameters of non-unitary pairing states of the putative spin-triplet superconductor UTe$_2$. We consider all symmetry-allowed non-unitary states under magnetic fields comprehensively, and calculate the anomalous Hall conductivity arising from time-reversal symmetry-breaking Weyl point nodes of the gap functions, assuming three types of Fermi surfaces; ellipsoid-shaped, cylinder-shaped, and ring-shaped ones, which are predicted by previous band calculations. We find the nonzero anomalous thermal Hall conductivity in the certain ratio of the two irreducible representations. The results may be utilized for future exploration of pairing states of UTe$_2$.