Theory of Open Quantum Systems as Applied to Spin Relaxation in Solids

TL;DR

This paper applies open quantum system theory to derive microscopic Bloch equations for electron spin relaxation in semiconductors, explicitly relating relaxation times to material properties and scattering mechanisms.

Contribution

It provides a microscopic derivation of spin relaxation times using open quantum system methods, including effects of phonons and impurities in magnetic fields.

Findings

Explicit formulas for spin relaxation times in terms of material constants.

Agreement with previous phenomenological models in zero magnetic field.

Inclusion of phonon and impurity scattering effects.

Abstract

We employ the method of the theory of open quantum systems to analyze spin relaxation and decoherence in semiconductors in the presence of a magnetic field. We derive a set of Bloch equations for electron spin with a fully microscopic determination of longitudinal and transverse relaxation times. Electron scattering from optical and acoustic phonons and random impurities is taken into account. We obtain explicit expressions for the spin relaxation times in terms of material constants and coupling strengths, exhibiting formal agreement with earlier treatments in the zero magnetic field limit with microscopic specification of their phenomenological parameters.