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arXiv · 1909.11550

Dimerization-induced topological superconductivity in a Rashba nanowire

Aksel Kobiałka·Nicholas Sedlmayr·Maciej M. Maśka·Tadeusz Domański
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Abstract

We analyze influence of a dimerization on the topological phases of the Rashba nanowire proximitized to a superconducting substrate. We find that periodic alternations of the hopping integral and spin-orbit coupling can lead to band inversion, inducing transition to topologically nontrivial superconducting phase that hosts the Majorana zero-energy modes. This "dimerization-induced topological superconductivity" completely repels the topological phase of the uniform nanowire, whenever they happen to overlap. We provide an analytical justification for this puzzling behavior based on the symmetry/parity considerations and discuss feasible spectroscopic methods for its empirical observation. We also test stability of the topological superconducting phases against electrostatic disorder.

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Aksel Kobiałka, Nicholas Sedlmayr, Maciej M. Maśka, Tadeusz Domański. 2019-09-25. Dimerization-induced topological superconductivity in a Rashba nanowire. https://doi.org/10.1103/physrevb.101.085402

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