Unique Spin Vortices in Quantum Dots with Spin-orbit Couplings

TL;DR

This paper uncovers the existence of stable spin vortices with different topological charges in quantum dots with spin-orbit couplings, even at the single-electron level, and demonstrates their robustness under various conditions.

Contribution

It reveals the presence of topologically distinct spin vortices in quantum dots with spin-orbit interactions, a phenomenon previously unreported at the single-electron level.

Findings

Spin vortices with different topological charges exist in quantum dots.

These spin textures are stable in the ground state.

The phenomena persist with electron interactions and magnetic fields.

Abstract

Spin textures of one or two electrons in a quantum dot with Rashba or Dresselhaus spin-orbit couplings reveal several intriguing properties. We show that even at the single-electron level spin vortices with different topological charges exist. These topological textures appear in the {\it ground state} of the dots. The textures are stabilized by time-reversal symmetry breaking and are robust against the eccentricity of the dot. The phenomenon persists for the interacting two-electron dot in the presence of a magnetic field.