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arXiv · 2503.11525

Slow magnetic quantum oscillations in the c-axis magnetoresistance of UTe$_2$

Freya Husstedt·Motoi Kimata·Sajal Naduvile Thadathil·Beat Valentin Schwarze·Markus König·Gerard Lapertot·Jean-Pascal Brison·Georg Knebel·Dai Aoki·J. Wosnitza·Toni Helm
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Abstract

Details of the electronic band structure in unconventional superconductors are key to the understanding of their fundamental ground state. The potential spin-triplet superconductor UTe$_2$, with $T_\mathrm{c}\approx 2.1\,$K, has attracted attention recently. Its main Fermi surface consists of weakly corrugated, two-dimensional Fermi-surface cylinders that run along the crystallographic $c$ axis. In addition, there is evidence for the presence of an additional small three-dimensional band. This has been discussed controversially as it may be essential for the realization of superconductivity in UTe$_2$. Here, we investigate the angle-resolved magnetoresistance and Hall effect in bulk crystalline samples with current along the $c$ axis in fields up to $60\,$T. We observe low-frequency magnetic quantum oscillations with light effective masses that are most pronounced for magnetic field applied along the $a$ axis. Two distinct frequencies indicate two separate changes in the Fermi-surface topology, likely connected with Lifshitz transitions. We discuss the origin of these oscillations in terms of magnetic breakdown, quantum interference, and other potential mechanisms.

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Freya Husstedt, Motoi Kimata, Sajal Naduvile Thadathil, Beat Valentin Schwarze, Markus König, Gerard Lapertot, Jean-Pascal Brison, Georg Knebel, Dai Aoki, J. Wosnitza, Toni Helm. 2025-03-14. Slow magnetic quantum oscillations in the c-axis magnetoresistance of UTe$_2$. https://doi.org/10.1103/nv42-w4t7

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