The Coulomb impurity in 2D materials with strong spin-orbit interaction

TL;DR

This paper demonstrates that Coulomb fields of charged impurities can induce bound states in 2D materials with strong spin-orbit interaction, especially when local symmetry breaking enhances Rashba SOI.

Contribution

It introduces a novel mechanism where Coulomb impurity fields create bound states via spin-orbit interaction in 2D materials with broken inversion symmetry.

Findings

Coulomb impurity fields can generate bound states through SOI

Strong Rashba SOI enhances impurity-bound state formation

Local symmetry breaking is crucial for the mechanism

Abstract

We show that the spin-orbit interaction (SOI) produced by the Coulomb fields of charged impurities provides an efficient mechanism for the bound states formation. The mechanism can be realized in 2D materials with sufficiently strong Rashba SOI provided that the impurity locally breaks the structure inversion symmetry in the direction normal to the layer.