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arXiv · 2510.19404

Anisotropic collapse of electronic correlations in the ferromagnet UGe$_2$ under high magnetic field

K. Somesh·T. Thebault·V. Taufour·D. Aoki·F. Duc·G. Knebel·D. Braithwaite·W. Knafo
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Abstract

We present electrical-resistivity measurements on the prototypical heavy-fermion ferromagnet UGe$_2$ under pulsed magnetic field up to 60~T. An anisotropic field-induced suppression of the electronic correlations is revealed. The electrical resistivity strongly decreases when a magnetic field $\mathbf{H}$ is applied along the easy magnetic axis $\mathbf{a}$, while it remains almost unchanged when $\mathbf{H}$ is applied along the hard magnetic axes $\mathbf{b}$ and $\mathbf{c}$. The field-induced destabilization of the ferromagnetic state is also anisotropic: the anomaly at the Curie temperature $T_C$ disappears in fields higher than $\gtrsim1$~T for $\mathbf{H}\parallel\mathbf{a}$ and in fields higher than $\gtrsim20$~T for $\mathbf{H}\parallel\mathbf{b},\mathbf{c}$. At temperatures below 2~K, we observe quantum oscillations in fields larger than 50~T applied along $\mathbf{b}$, which support the presence of a two-dimensional Fermi surface similar to that previously observed at low fields.

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K. Somesh, T. Thebault, V. Taufour, D. Aoki, F. Duc, G. Knebel, D. Braithwaite, W. Knafo. 2025-10-22. Anisotropic collapse of electronic correlations in the ferromagnet UGe$_2$ under high magnetic field. https://doi.org/10.1103/nw84-wh8h

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