Josephson current through a quantum dot with spin-orbit coupling

TL;DR

This paper investigates how spin-orbit coupling affects the Josephson current in a quantum dot, revealing significant modifications and oscillatory behaviors under magnetic fields, with potential implications for quantum device control.

Contribution

It provides the first detailed analysis of the impact of Rashba and Dresselhaus spin-orbit coupling on the Josephson current in multi-level quantum dots, including Zeeman field effects.

Findings

Critical current is significantly altered by moderate spin-orbit coupling.

Oscillatory dependencies on spin-orbit strength are predicted under Zeeman fields.

Spin-orbit coupling can be used to control Josephson current properties.

Abstract

The equilibrium Josephson current through a nanoscale multi-level quantum dot with Rashba or Dresselhaus spin-orbit coupling $\alpha$ has been computed. The critical current can be drastically modified already by moderate $\alpha$. In the presence of a Zeeman field, Datta-Das-like oscillatory dependencies on $\alpha$ are predicted.