# Magnetic-field orientation dependence of transport properties of topologically superconducting wire

## TL;DR

This paper investigates how the orientation of an external magnetic field affects the transport properties of a topologically superconducting wire with strong Rashba spin-orbit coupling, revealing effects like conductance variation, current-switching, and spin filtering.

## Contribution

It provides a detailed analysis of the impact of magnetic field orientation on transport phenomena in topological superconductors, including conductance, shot noise, and spin-filtering effects, using nonequilibrium Green's functions.

## Key findings

- Transport regime varies from symmetric to asymmetric depending on magnetic field orientation.
- Current-symmetry breaking and conductance suppression lead to a current-switch effect.
- Spin-filtering effect depends on magnetic-field orientation and persists under disorder.

## Abstract

We present the study of transport properties of a superconducting wire with strong Rashba spin-orbit coupling for different orientations of an external magnetic field. Using the nonequilibrium Green's functions in the tight-binding approach the crucial impact of the relative alignment of lead magnetization and the Majorana bound state (MBS) spin polarization on the low-bias conductance and shot noise is presented. Depending on this factor the transport regime can effectively vary from symmetric to extremely asymmetric. In the last situation the current-symmetry breaking, the suppression of the MBS-assisted conductance and specific Fano factor behavior lead to current-switch effect. The persistence of these features under the presence of diagonal disorder and phenomenologically modeled g-factor anisotropy is demonstrated. In the case of paramagnetic leads the MBS spin polarization gives rise to the spin-filtering effect depending on the magnetic-field orientation.