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arXiv · 1904.06275

Optimized micromagnet geometries for Majorana zero modes in low g-factor materials

Sara Turcotte·Samuel Boutin·Julien Camirand Lemyre·Ion Garate·Michel Pioro-Ladrière
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Abstract

Solid-state experimental realizations of Majorana bound states are based on materials with strong intrinsic spin-orbit interactions. In this paper, we explore an alternative approach where spin-orbit coupling is induced artificially through a nonuniform magnetic field that originates from an array of micromagnets. Using a recently developed optimization algorithm, we find suitable magnet geometries for the emergence of topological superconductivity in wires without intrinsic spin-orbit coupling. We confirm the robustness of Majorana bound states against disorder and periodic potentials whose amplitudes do not exceed the Zeeman energy. Furthermore, we identify low g-factor materials commonly used in mesoscopic physics experiments as viable candidates for Majorana devices.

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Sara Turcotte, Samuel Boutin, Julien Camirand Lemyre, Ion Garate, Michel Pioro-Ladrière. 2021-02-03. Optimized micromagnet geometries for Majorana zero modes in low g-factor materials. https://doi.org/10.1103/physrevb.102.125425

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