Spin-selective coupling to Majorana zero modes in mixed singlet and triplet superconducting nanowires

摘要

We theoretically investigate the transport properties of a quasi-one-dimensional ferromagnet-superconductor junction where the superconductor consists of mixed singlet and triplet pairings. We show that the relative orientation of the Stoner field (h) in the ferromagnetic lead and the d vector of the superconductor acts like a on-off switch for the zero bias conductance of the device. In the regime, where triplet pairing amplitude dominates over the singlet counterpart (topological phase), a pair of Majorana zero modes appear at each end of the superconducting part of the nanowire. When h is parallel or antiparallel to the d vector, transport gets completely blocked due to blockage in pairing while, when h and d are perpendicular to each other, the zero energy two terminal differential conductance spectra exhibits sharp transition from 4e~2/h to 2e~2/h as the magnetization strength in the lead becomes larger than the chemical potential indicating the spin-selective coupling of a pair of Majorana zero modes to the lead.