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arXiv · 2107.02706

Thermodynamic signatures of short-range magnetic correlations in UTe$_2$

Kristin Willa·Frédéric Hardy·Dai Aoki·Dexin Li·Paul Wiecki·Gérard Lapertot·Christoph Meingast
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Abstract

The normal-state out of which unconventional superconductivity in UTe$_2$ emerges is studied in detail using a variety of thermodynamic and transport probes. Clear evidence for a broad Schottky-like anomaly with roughly R ln 2 entropy around $T^{*} \approx 12$K is observed in all measured quantities. Comparison with high magnetic field transport data allows the construction of an $H\text{-}T$ phase diagram resembling that of the ferromagnetic superconductor URhGe. The low field electronic Grüneisen parameter of $T^{*}$ and that of the metamagnetic transition at $H_m \approx 35$T are comparable pointing to a common origin of both phenomena. Enhanced Wilson and Korringa ratios suggests that the existence of short range ferromagnetic fluctuations cannot be ruled out.

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Kristin Willa, Frédéric Hardy, Dai Aoki, Dexin Li, Paul Wiecki, Gérard Lapertot, Christoph Meingast. 2021-07-06. Thermodynamic signatures of short-range magnetic correlations in UTe$_2$. https://doi.org/10.1103/physrevb.104.205107

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