Combined effect of Zeeman splitting and spin-orbit interaction on the Josephson current in a S-2DEG-S structure

TL;DR

This paper investigates how Zeeman splitting and spin-orbit interaction influence the Josephson current in a superconductor-2DEG-superconductor structure, revealing interference patterns and anisotropic effects useful for probing spin-orbit strength.

Contribution

It introduces a detailed analysis of combined Zeeman and spin-orbit effects on Josephson current, highlighting conditions for pi-junction behavior and anisotropic current dependence.

Findings

Zeeman splitting causes supercurrent oscillations over magnetic field B.

Spin-orbit interaction induces anisotropic Josephson current dependence.

System can exhibit pi-junction properties under specific conditions.

Abstract

We analyze new spin effects in current-carrying state of superconductor-2D electron gas-superconductor (S-2DEG-S) device with spin-polarized nuclei in 2DEG region. The hyperfine interaction of 2D electrons with nuclear spins, described by the effective magnetic field B, produces Zeeman splitting of Andreev levels without orbital effects, that leads to the interference pattern of supercurrent oscillations over B. The spin-orbit effects in 2DEG cause strongly anisotropic dependence of the Josephson current on the direction of B, which may be used as a probe for the spin-orbit interaction intensity. Under certain conditions, the system reveals the properties of pi-junction.