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arXiv · 2102.07512

Fermi-surface reconstruction at the metamagnetic high-field transition in uranium mononitride

Sandra Hamann·Tobias Förster·Denis. I. Gorbunov·Markus König·Marc Uhlarz·Joachim Wosnitza·Toni Helm
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Abstract

We report on the electronic and thermodynamic properties of the antiferromagnetic metal uranium mononitride with a Néel temperature $T_N\approx 53\,$K. The fabrication of microstructures from single crystals enables us to study the low-temperature metamagnetic transition at approximately $58\,$T by high-precision magnetotransport, Hall-effect, and magnetic-torque measurements. We confirm the evolution of the high-field transition from a broad and complex behavior to a sharp first-order-like step, associated with a spin flop at low temperature. In the high-field state, the magnetic contribution to the temperature dependence of the resistivity is suppressed completely. It evolves into an almost quadratic dependence at low temperatures indicative of a metallic character. Our detailed investigation of the Hall effect provides evidence for a prominent Fermi-surface reconstruction as the system is pushed into the high-field state.

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Sandra Hamann, Tobias Förster, Denis. I. Gorbunov, Markus König, Marc Uhlarz, Joachim Wosnitza, Toni Helm. 2021-08-17. Fermi-surface reconstruction at the metamagnetic high-field transition in uranium mononitride. https://doi.org/10.1103/physrevb.104.155123

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