Topological Superconductivity Mediated by Skyrmionic Magnons

Topological superconductors are associated with the appearance of Majorana bound states, with promising applications in topologically protected quantum computing. In this Letter [1], we study a system where a skyrmion crystal is interfaced with a normal metal. Through interfacial exchange coupling, spin fluctuations in the skyrmion crystal mediate an effective electron-electron interaction in the normal metal. We study superconductivity within a weak-coupling approach and solve gap equations both close to the critical temperature and at zero temperature. Special features in the effective electron-electron interaction due to the noncolinearity of the magnetic ground state yield topological superconductivity at the interface. [1] K. Mæland and A. Sudbø, Topological Superconductivity Mediated by Skyrmionic Magnons, Phys. Rev. Lett. 130, 156002 (2023). Note: Editors' Suggestion, Featured in Physics: https://physics.aps.org/articles/v16/s53