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arXiv · 2002.05236

Volkov-Pankratov states in topological superconductors

David J. Alspaugh·Daniel E. Sheehy·Mark O. Goerbig·Pascal Simon
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Abstract

We study the in-gap states that appear at the boundaries of both 1D and 2D topological superconductors. While the massless Majorana quasiparticles are guaranteed to arise by the bulk-edge correspondence, we find that they could be accompanied by massive Volkov-Pankratov (VP) states which are present only when the interface is sufficiently smooth. These predictions can be tested in an s-wave superconductor with Rashba spin-orbit coupling placed on top of a magnetic domain wall. We calculate the spin-resolved local density of states of the VP states about the band inversion generated by a magnetic domain wall and find that they are oppositely spin-polarized on either side of the topological phase boundary. We also demonstrate that the spatial position, energy-level spacing, and spin polarization of the VP states can be modified by the introduction of in-plane electric fields.

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David J. Alspaugh, Daniel E. Sheehy, Mark O. Goerbig, Pascal Simon. 2020-02-12. Volkov-Pankratov states in topological superconductors. https://doi.org/10.1103/physrevresearch.2.023146

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