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arXiv · 2105.09317

Using Disorder to Identify Bogoliubov Fermi-Surface States

Hanbit Oh·Daniel F. Agterberg·Eun-Gook Moon
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Abstract

We argue that a superconducting state with a Fermi-surface of Bogoliubov quasiparticles, a Bogoliubov Fermi-surface (BG-FS), can be identified by the dependence of physical quantities on disorder. In particular, we show that a linear dependence of the residual density of states at weak disorder distinguishes a BG-FS state from other nodal superconducting states. We further demonstrate the stability of supercurrent against impurities and a characteristic Drude-like behavior of the optical conductivity. Our results can be directly applied to electron irradiation experiments on candidate materials of BG-FSs, including Sr$_2$RuO$_4$, FeSe$_{1-x}$S$_x$, and UBe$_{13}$.

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Hanbit Oh, Daniel F. Agterberg, Eun-Gook Moon. 2021-12-23. Using Disorder to Identify Bogoliubov Fermi-Surface States. https://doi.org/10.1103/physrevlett.127.257002

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