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arXiv · 2211.08354

Lattice Instability of UTe$_2$ Studied by Ultrasonic Measurements

Keita Ushida·Tatsuya Yanagisawa·Ruo Hibino·Masato Matsuda·Hiroyuki Hidaka·Hiroshi Amitsuka·Georg Knebel·Jacques Flouquet·Dai Aoki
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Abstract

The elastic constants of an unconventional superconductor, UTe$_2$, were investigated using ultrasound. In this paper, we report the elastic response of the normal state at temperatures down to 2 K and up to 14 T for $H \parallel b$ at ambient pressure. The transverse ultrasonic mode $C_{55}$, which corresponds to the strain susceptibility of $\varepsilon_{zx}$, shows softening with decreasing temperature, whereas the $C_{44}$ and $C_{33}$ modes do not show such softening. This clear mode dependence strongly suggests that UTe$_2$ has a lattice instability for this specific symmetry.

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Keita Ushida, Tatsuya Yanagisawa, Ruo Hibino, Masato Matsuda, Hiroyuki Hidaka, Hiroshi Amitsuka, Georg Knebel, Jacques Flouquet, Dai Aoki. 2022-11-12. Lattice Instability of UTe$_2$ Studied by Ultrasonic Measurements. https://doi.org/10.7566/jpscp.38.011021

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