# Non-linear spin filter for non-magnetic materials at zero magnetic field

## TL;DR

This paper introduces a novel all-electrical, non-invasive method for detecting spin accumulation in non-magnetic materials at zero magnetic field, utilizing non-linear spin-charge interactions in systems with strong spin-orbit coupling.

## Contribution

It presents a new technique exploiting non-linear interactions for spin detection without magnetic fields, demonstrated with ballistic GaAs holes and a quantum point contact.

## Key findings

- Effective spin-to-charge conversion demonstrated
- Operates without magnetic field or large magnetic field
- Applicable to various spin-orbit coupled systems

## Abstract

The ability to convert spin accumulation to charge currents is essential for applications in spintronics. In semiconductors, spin-to-charge conversion is typically achieved using the inverse spin Hall effect or using a large magnetic field. Here we demonstrate a general method that exploits the non-linear interactions between spin and charge currents to perform all-electrical, rapid and non-invasive detection of spin accumulation without the need for a magnetic field. We demonstrate the operation of this technique with ballistic GaAs holes as a model system with strong spin-orbit coupling, in which a quantum point contact provides the non-linear energy filter. This approach is generally applicable to electron and hole systems with strong spin orbit coupling.