Chiral superconductivity in a semiconducting wire induced by helical magnetic order

Abstract

Chiral superconductors are sought after for their promising but elusive Majorana zero modes. We show that a one-dimensional semiconductor in proximity to a conventional superconductor and a helical magnet can exhibit chiral superconductivity, without the need for external magnetic fields or intrinsic spin-orbit coupling. The effective proximity-induced gap and the triplet gap arising from magnon fluctuations can be made to interfere constructively. The heterostructure can be tuned into a topological regime with Majorana zero modes at its ends, over a range of chemical potentials proportional to the spin-electron coupling.