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arXiv · 2210.11955

Helical Topological Superconducting Pairing at Finite Excitation Energies

Masoud Bahari·Song-Bo Zhang·Chang-An Li·Sang-Jun Choi·Philipp Rüßmann·Carsten Timm·Björn Trauzettel
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Abstract

We propose helical topological superconductivity away from the Fermi surface in three-dimensional time-reversal-symmetric odd-parity multiband superconductors. In these systems, pairing between electrons originating from different bands is responsible for the corresponding topological phase transition. Consequently, a pair of helical topological Dirac surface states emerges at finite excitation energies. These helical Dirac surface states are tunable in energy by chemical potential and strength of band-splitting. They are protected by time-reversal symmetry combined with crystalline two-fold rotation symmetry. We suggest concrete materials in which this phenomenon could be observed.

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Masoud Bahari, Song-Bo Zhang, Chang-An Li, Sang-Jun Choi, Philipp Rüßmann, Carsten Timm, Björn Trauzettel. 2022-10-21. Helical Topological Superconducting Pairing at Finite Excitation Energies. https://doi.org/10.1103/physrevlett.132.266201

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