Transverse Electron Focusing in Systems with Spin-Orbit Coupling

TL;DR

This paper investigates how spin-orbit coupling influences transverse electron focusing in 2D electron gases, revealing a spin-dependent splitting of focusing peaks that varies with material properties.

Contribution

It demonstrates the impact of Rashba spin-orbit coupling on electron focusing, showing spin polarization effects and peak splitting in different material systems.

Findings

Splitting of the first focusing peak into two spin-polarized contributions.

Surface reflection affects the second focusing peak.

Material-dependent visibility of the effect, prominent in InSb/InAlSb.

Abstract

We study the transverse electron focusing in a two dimensional electron gas with Rashba spin-orbit coupling. We show that the interplay between the external magnetic field and the spin-orbit coupling gives two branches of states with different cyclotron radius within the same energy window. This effect generates a splitting of the first focusing peak in two contributions. Each one of these contributions is spin polarized. The surface reflection mixes the two branches and the second focusing peak does not present the same effect. While for GaAs/AlGaAs heterostructures the effect is small, in systems like InSb/InAlSb the effect should be clearly observed.