# Spin-dependent conductance statistics in systems with spin-orbit coupling

## TL;DR

This paper investigates how spin-orbit coupling affects spin-dependent conductance in electron transport systems, revealing conditions under which spin polarization is maximized or preserved despite disorder and system length.

## Contribution

It provides a detailed analysis of spin-dependent conductance statistics in systems with varying spin-orbit interactions and disorder, highlighting novel effects like spin-filtering and polarization behavior.

## Key findings

- Maximum polarization occurs at specific SO coupling strengths.
- Polarization remains stable with increasing system length under certain disorder conditions.
- Spin-filter effect observed with low disorder and weak SO coupling.

## Abstract

Spin-dependent partial conductances are evaluated in a tight-binding description of electron transport in the presence of spin-orbit (SO) couplings, using transfer-matrix methods. As the magnitude of SO interactions increases, the separation of spin-switching channels from non-spin-switching ones is gradually erased. Spin-polarised incident beams are produced by including a Zeeman-like term in the Hamiltonian. The exiting polarisation is shown to exhibit a maximum as a function of the intensity of SO couplings. For moderate site disorder, and both weak and strong SO interactions, no evidence is found for a decay of exiting polarisation against increasing system length. With very low site disorder and weak SO couplings a spin-filter effect takes place, as polarisation {\em increases} with increasing system length.