Topological Superconductivity From Forward Phonon Scatterings

Shaozhi Li; Lun-Hui Hu; Rui-Xing Zhang; Satoshi Okamoto

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arXiv · 2207.09443

Topological Superconductivity From Forward Phonon Scatterings

Shaozhi Li·Lun-Hui Hu·Rui-Xing Zhang·Satoshi Okamoto

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Abstract

We propose a new Rashba-free mechanism to realize topological superconductivity with electron-phonon interaction. In the presence of a magnetic field, electron-phonon interaction with small momentum transfer is found to favor spin-triplet Cooper pairing. This process facilitates the formation of chiral topological superconductivity even when Rashba spin-orbital coupling is absent. As a proof of concept, we propose an experimentally feasible heterostructure to systematically study the entangled relationship among forward-phonon scatterings, Rashba spin-orbital couplings, pairing symmetries, and superconducting topology. Our theory sheds light on the important role of electron-phonon coupled materials in the pursuit of non-Abelian Majorana quasiparticles.

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Shaozhi Li, Lun-Hui Hu, Rui-Xing Zhang, Satoshi Okamoto. 2022-07-19. Topological Superconductivity From Forward Phonon Scatterings. https://arxiv.org/abs/2207.09443

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