Supercurrent-induced topological phase transitions

Kazuaki Takasan; Shuntaro Sumita; Youichi Yanase

doi:10.1103/physrevb.106.014508

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arXiv · 2110.06959

Supercurrent-induced topological phase transitions

Kazuaki Takasan·Shuntaro Sumita·Youichi Yanase

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Abstract

We show that finite current in superconductors can induce topological phase transitions, as a result of the deformation of the quasiparticle spectrum by a finite center-of-mass (COM) momentum of the Cooper pairs. To show the wide applicability of this mechanism, we examine the topological properties of three prototypical systems, the Kitaev chain, $s$-wave superconductors, and $d$-wave superconductors. We introduce a finite COM momentum as an external field corresponding to supercurrent and show that all the models exhibit current-induced topological phase transitions. We also discuss the possibility of observing the phase transitions in experiments and the relation to the other finite COM momentum pairing states.

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Kazuaki Takasan, Shuntaro Sumita, Youichi Yanase. 2021-10-13. Supercurrent-induced topological phase transitions. https://doi.org/10.1103/physrevb.106.014508

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