# Quantum Spin Hall Effect in Electric and Magnetic Fields without Spin-Orbit Coupling

## TL;DR

This paper demonstrates the quantum spin Hall effect in 2D metals without relying on spin-orbit coupling, highlighting the role of anisotropy and Zeeman interaction in such systems.

## Contribution

It reveals the possibility of observing QSHE without spin-orbit coupling and emphasizes the impact of anisotropic motion and Zeeman interaction on the effect.

## Key findings

- QSHE can occur in 2D metals without spin-orbit coupling
- Anisotropy of electron motion significantly influences QSHE
- Zeeman interaction dimensionality alters measurement interpretations

## Abstract

From the Dirac equation of an electron in an anisotropic conduction band, the anisotropy of its motion dramatically affects its interaction with applied electric and magnetic fields. The quantum spin Hall effect (QSHE) is observable in two-dimensional metals without spin-orbit coupling. The dimensionality of the Zeeman interaction plays an important role in the QSHE, and profoundly modifies many interpretations of measurements of the Knight shift and of the upper critical field in highly anisotropic superconductors.