Anderson transition of cold atoms with synthetic spin-orbit coupling in two-dimensional speckle potentials

TL;DR

This paper studies the metal-insulator transition in 2D cold atom systems with synthetic spin-orbit coupling and speckle disorder, identifying the transition's universality class and how it depends on coupling parameters.

Contribution

It provides a precise calculation of the mobility edge and reveals the dependence of the transition on the spin-orbit coupling mixing angle.

Findings

The transition belongs to the symplectic universality class.

The mobility edge varies strongly with the Rashba-Dresselhaus mixing angle.

A non-power-law divergence indicates a crossing to the orthogonal class.

Abstract

We investigate the metal-insulator transition occurring in two-dimensional (2D) systems of noninteracting atoms in the presence of artificial spin-orbit interactions and a spatially correlated disorder generated by laser speckles. Based on a high order discretization scheme, we calculate the precise position of the mobility edge and verify that the transition belongs to the symplectic universality class. We show that the mobility edge depends strongly on the mixing angle between Rashba and Dresselhaus spin-orbit couplings. For equal couplings a non-power-law divergence is found, signaling the crossing to the orthogonal class, where such a 2D transition is forbidden.