Magneto-thermal evidence of a partial gap at the Fermi surface of UPt_2Si_2

TL;DR

This study investigates the thermoelectric properties of UPt_2Si_2, revealing a Nernst effect anomaly linked to antiferromagnetic order, suggesting a partial Fermi surface gap similar to URu_2Si_2.

Contribution

It provides the first thermoelectric transport analysis of UPt_2Si_2, identifying a Nernst effect anomaly associated with magnetic ordering and partial Fermi surface gapping.

Findings

Nernst effect anomaly coincides with antiferromagnetic transition

Partial Fermi surface gap inferred from thermoelectric response

Comparison with URu_2Si_2 highlights common electronic features

Abstract

Motivated by the observation of a giant Nernst effect in URu_2Si_2, the thermoelectric response of the related system UPt_2Si_2 was investigated using thermal and electric transport properties such as the Nernst and Seebeck effects, thermal conductivity, Hall effect and electrical resitivity. Unlike URu_2Si_2, UPt_2Si_2 is neither superconducting nor exhibits a ``hidden-order'' state. Nevertheless a pronounced Nernst effect anomaly is found to coincide with the onset of the antiferromagnetic order in UPt_2Si_2. Although the absolute values are substantially lower, its appearance and characteristics can favorably be compared to the giant Nernst effect in URu_2Si_2 indicating the common feature of a partial Fermi surface gap.