Magnetic breakdown of cyclotron orbits in systems with Rashba and Dresselhaus spin-orbit coupling

TL;DR

This paper investigates how Rashba and Dresselhaus spin-orbit couplings influence electron focusing in 2D systems, revealing magnetic breakdown phenomena and interference effects that can be experimentally observed.

Contribution

It demonstrates the impact of combined spin-orbit couplings on electron orbit splitting and tunneling, highlighting the magnetic breakdown effect in 2D electron gases.

Findings

Splitting of the first focusing peak into two or three peaks.

Presence of a third peak related to magnetic breakdown.

Interference effects observable in second focusing condition.

Abstract

We study the effect of the interplay between the Rashba and the Dresselhaus spin-orbit couplings on the transverse electron focusing in two-dimensional electron gases. Depending on their relative magnitude, the presence of both couplings can result in the splitting of the first focusing peak into two or three. This splitting has information about the relative value of spin-orbit couplings and therefore about the shape of the Fermi surface. More interesting, the presence of the third peak is directly related to the tunneling probability ("magnetic breakdown") between orbits corresponding to the different sheets of the Fermi surface. In addition, destructive interference effects between paths that involve tunneling and those that do not can be observed in the second focusing condition. Such electron paths (orbits) could be experimentally detected using current techniques for imaging the electron flow opening the possibility to directly observe and characterize the magnetic breakdown effect in this system.