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

  • Sara Turcotte ,
  • Samuel Boutin ,
  • Julien Camirand Lemyre ,
  • Ion Garate ,
  • Michel Pioro-Ladrière

2020 Physical Review B | , Vol 102(12): pp. 125425

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.