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arXiv · 1904.07822

Braiding Majorana corner modes in a second-order topological superconductor

Tudor E. Pahomi·Manfred Sigrist·Alexey A. Soluyanov
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Abstract

We propose the concept of a device based on a square-shaped sample of a two-dimensional second-order topological helical superconductor which hosts two zero-dimensional Majorana quasiparticles at the corners. The two zero-energy modes rely on particle-hole symmetry (PHS) and their spacial position can be shifted by rotating an in-plane magnetic field and tuning proximity-induced spin-singlet pairing. We consider an adiabatic cycle performed on the degenerate ground-state manifold and show that it realizes the braiding of the two modes whereby they accumulate a non-trivial statistical phase $\pi$ within one cycle. Alongside with the PHS-ensured operator algebra, the fractional statistics confirms the Majorana nature of the zero-energy excitations. A schematic design for a possible experimental implementation of such a device is presented, which could be a step towards realizing non-Abelian braiding.

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Tudor E. Pahomi, Manfred Sigrist, Alexey A. Soluyanov. 2019-04-16. Braiding Majorana corner modes in a second-order topological superconductor. https://doi.org/10.1103/physrevresearch.2.032068

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