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arXiv · 2408.14619

Connection between f-electron correlations and magnetic excitations in UTe2

Thomas Halloran·Peter Czajka·Gicela Saucedo Salas·Corey Frank·Chang-Jong Kang·J. A. Rodriguez-Rivera·Jakob Lass·Daniel G. Mazzone·Marc Janoschek·Gabi Kotliar·Nicholas P. Butch
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Abstract

The detailed anisotropy of the low-temperature, low-energy magnetic excitations of the candidate spin-triplet superconductor UTe$_2$ is revealed using inelastic neutron scattering. The magnetic excitations emerge from the Brillouin zone boundary at the high symmetry $Y$ and $T$ points and disperse along the crystallographic $\hat{b}$-axis. In applied magnetic fields to at least $\mu_0 H=11$~T along the $\hat{c}-$axis, the magnetism is found to be field-independent in the $(hk0)$ plane. The scattering intensity is consistent with that expected from U$^{3+}$/U$^{4+}$ $f$-electron spins with preferential orientation along the crystallographic $\hat{a}$-axis, and a fluctuating magnetic moment of 2.3(7) $\mu_B$. These characteristics indicate that the excitations are due to intraband spin excitons arising from $f$-electron hybridization.

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Thomas Halloran, Peter Czajka, Gicela Saucedo Salas, Corey Frank, Chang-Jong Kang, J. A. Rodriguez-Rivera, Jakob Lass, Daniel G. Mazzone, Marc Janoschek, Gabi Kotliar, Nicholas P. Butch. 2024-08-26. Connection between f-electron correlations and magnetic excitations in UTe2. https://arxiv.org/abs/2408.14619

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