Spin Splitting in Symmetrical SiGe Quantum Wells

TL;DR

This paper analyzes spin splitting in symmetrical SiGe quantum wells, highlighting how interface asymmetry causes Rashba and Dresselhaus spin splitting, impacting spin relaxation mechanisms.

Contribution

It provides a comprehensive analysis of spin splitting due to interface asymmetry in symmetrical SiGe quantum wells, including both Rashba and Dresselhaus effects.

Findings

Spin splitting occurs in symmetrical SiGe quantum wells due to interface asymmetry.

Both Rashba and Dresselhaus types of spin splitting are present.

Spin splitting influences spin relaxation processes.

Abstract

Spin splitting of conduction electron states has been analyzed for all possible point symmetries of SiGe quantum well structures. A particular attention is paid to removal of spin degeneracy caused by the rotoinversion asymmetry of a (001) heterointerface between two diamond-lattice materials. The asymmetry is shown to result in spin splitting of both Rashba and Dresselhaus types in symmetrical SiGe quantum wells. Consequences of the spin splitting on spin relaxation are discussed.