Enhancement and Discontinuity of Effective Mass through the First-Order Metamagnetic Transition in UTe$_2$

Atsushi Miyake; Yusei Shimizu; Yoshiki J. Sato; Dexin Li; Ai Nakamura; Yoshiya Homma; Fuminori Honda; Jacques Flouquet; Masashi Tokunaga; Dai Aoki

doi:10.7566/jpsj.90.103702

arXiv · 2108.08509

Enhancement and Discontinuity of Effective Mass through the First-Order Metamagnetic Transition in UTe$_2$

Atsushi Miyake·Yusei Shimizu·Yoshiki J. Sato·Dexin Li·Ai Nakamura·Yoshiya Homma·Fuminori Honda·Jacques Flouquet·Masashi Tokunaga·Dai Aoki

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Abstract

Metamagnetic transitions in the novel spin-triplet superconductor UTe$_2$ were investigated through the newly developed simultaneous measurements of magnetization and sample temperature for the field along the orthorhombic $b$-axis and close to the [011] direction, where reentrant superconductivity (RSC) is detected below and above the first-order metamagnetic transition field $H_{\rm m}$. Combining the Maxwell's relation and the Clausius-Clapeyron equation, we obtained the field dependence of Sommerfeld coefficient $\gamma$ through the first-order metamagnetic transition. A significant enhancement of the effective mass toward $H_{\rm m}$ were detected for both field directions. On the other hand, above $H_{\rm m}$, the effective mass discontinuously decreases for $H~||~b$, while it discontinuously increases for $H~||~\sim [011]$, which seems to make a crucial role for the RSC.

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Atsushi Miyake, Yusei Shimizu, Yoshiki J. Sato, Dexin Li, Ai Nakamura, Yoshiya Homma, Fuminori Honda, Jacques Flouquet, Masashi Tokunaga, Dai Aoki. 2021-08-19. Enhancement and Discontinuity of Effective Mass through the First-Order Metamagnetic Transition in UTe$_2$. https://doi.org/10.7566/jpsj.90.103702

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