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arXiv · 2303.09050

Revealing a 3D Fermi Surface Pocket and Electron-Hole Tunneling in UTe$_{2}$ with Quantum Oscillations

Christopher Broyles·Zack Rehfuss·Hasan Siddiquee·Jiahui Althena Zhu·Kaiwen Zheng·Martin Nikolo·David Graf·John Singleton·Sheng Ran
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Abstract

Spin triplet superconductor UTe$_{2}$ is widely believed to host a quasi-two-dimensional Fermi surface, revealed by first principal calculations, photoemission and quantum oscillation measurements. An outstanding question still remains as to the existence of a three-dimensional Fermi surface pocket, which is crucial for our understanding of the exotic superconducting and topological properties of UTe$_{2}$. This 3D Fermi surface pocket appears in various theoretical models with different physics origins but has not been detected experimentally. Here for the first time, we provide concrete evidence for a relatively isotropic, small Fermi surface pocket of UTe$_{2}$ via quantum oscillation measurements. In addition, we observed high frequency quantum oscillations corresponding to electron-hole tunneling between adjacent electron and hole pockets. The coexistence of 2D and 3D Fermi surface pockets, as well as the breakdown orbits, provides a test bed for theoretical models and aid the realization of a unified understanding of superconducting state of UTe$_{2}$ from the first-principles approach.

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Christopher Broyles, Zack Rehfuss, Hasan Siddiquee, Jiahui Althena Zhu, Kaiwen Zheng, Martin Nikolo, David Graf, John Singleton, Sheng Ran. 2023-03-16. Revealing a 3D Fermi Surface Pocket and Electron-Hole Tunneling in UTe$_{2}$ with Quantum Oscillations. https://doi.org/10.1103/physrevlett.131.036501

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