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arXiv · 1912.06784

Magnetic Flux Periodicity in Second Order Topological Superconductors

Suman Jyoti De·Udit Khanna·Sumathi Rao
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Abstract

The magnetic flux periodicity of $\frac{hc}{2e}$ is a well known manifestation of Cooper pairing in typical s-wave superconductors. In this paper we theoretically show that the flux periodicity of a two-dimensional second-order topological superconductor, which features zero-energy Majorana modes localized at the corners of the sample, is $\frac{hc}{e}$ instead. We further show that the periodicity changes back to $\frac{hc}{2e}$ at the transition to a topologically trivial superconductor, where the Majorana modes hybridize with the bulk states, demonstrating that the doubling of periodicity is a manifestation of the non-trivial topology of the state.

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Suman Jyoti De, Udit Khanna, Sumathi Rao. 2019-12-14. Magnetic Flux Periodicity in Second Order Topological Superconductors. https://doi.org/10.1103/physrevb.101.125429

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