# Doping-induced spin-orbit splitting in Bi-doped ZnO nanowires

## TL;DR

This study predicts that Bi doping in ZnO nanowires induces spin-orbit splitting of conduction electrons, which can be controlled electrically and tuned by dopant concentration, making them promising for spintronic devices.

## Contribution

It demonstrates that surface Bi doping causes linear spin-orbit splitting in ZnO nanowires, a novel way to control spin polarization electrically.

## Key findings

- Bi doping induces linear-in-k spin splitting.
- Spin splitting can be tuned by dopant concentration.
- Stable doping configurations are thermodynamically feasible.

## Abstract

Our predictions, based on density-functional calculations, reveal that surface doping of ZnO nanowires with Bi leads to a linear-in-$k$ splitting of the conduction-band states, through spin-orbit interaction, due to the lowering of the symmetry in the presence of the dopant. This finding implies that spin polarization of the conduction electrons in Bi-doped ZnO nanowires could be controlled with applied electric (as opposed to magnetic) fields, making them candidate materials for spin-orbitronic applications. Our findings also show that the degree of spin splitting could be tuned by adjusting the dopant concentration. Defect calculations and ab initio molecular dynamics simulations indicate that stable doping configurations exhibiting the foregoing linear-in-$k$ splitting could be realized under reasonable thermodynamic conditions.