Non-gapless excitation and zero-bias fast oscillations in the LDOS of surface superconducting states

Liangyuan Chen; Yajiang Chen; Zhang Wenhui; Zhou Shuhua

doi:10.1016/j.physb.2022.414302

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arXiv · 2307.12372

Non-gapless excitation and zero-bias fast oscillations in the LDOS of surface superconducting states

Liangyuan Chen·Yajiang Chen·Zhang Wenhui·Zhou Shuhua

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Abstract

Recently a novel surface pair-density-wave (PDW) superconducting state has been discovered in Refs. [Phys. Rev. Lett. \textbf{122}, 165302 (2019)] and Phys. Rev. B \textbf{101}, 054506 (2020)], which may go through a distinct multiple phase transition (MPT) when the superconductivity fades away from bulk to the boundary (e.g. edges and corners). Based on the Bogoliubov-de Gennes equations for the attractive tight-binding Hubbard modal in a one-dimensional chain, we demonstrate that the surface PDW state has a non-gapless quasiparticle spectrum, which is contrary to the conventional surface superconducting state. Moreover, we find that the MPT is associated with a zero-bias fast oscillating pattern in the LDOS near the surface. Our findings provide a potential experimental clue to identify the surface PDW state.

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Liangyuan Chen, Yajiang Chen, Zhang Wenhui, Zhou Shuhua. 2023-07-23. Non-gapless excitation and zero-bias fast oscillations in the LDOS of surface superconducting states. https://doi.org/10.1016/j.physb.2022.414302

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