Effect of Dresselhaus spin-orbit coupling on spin dephasing in asymmetric and macroscopically symmetric (110)-grown quantum wells

TL;DR

This paper develops a microscopic theory for electron spin dephasing in (110)-grown quantum wells, showing how Dresselhaus spin-orbit coupling can suppress dephasing and lead to long spin lifetimes, with a nonmonotonic dependence on electron mobility.

Contribution

It introduces a detailed microscopic model analyzing the influence of Dresselhaus and Rashba fields on spin dephasing in quantum wells, highlighting the conditions for extended spin lifetimes.

Findings

Dresselhaus field suppresses spin dephasing in quantum wells.

Spin lifetime depends nonmonotonically on electron mobility.

Maximum spin lifetime occurs when scattering time exceeds spin precession period.

Abstract

We develop the microscopic theory of electron spin dephasing in (110)-grown quantum wells where the electron scattering time is comparable to or exceeds the period of spin precession in the effective magnetic field caused by spin-orbit coupling. Structures with homogeneous and fluctuating Rashba field, which triggers the dephasing of electron spins aligned along the growth direction, are analyzed. We show that the Dresselhaus field, which is always present in zinc-blende-type quantum wells, suppresses the spin dephasing enabling very long spin lifetime of conduction electrons. The dependence of the spin lifetime on the electron mobility is found to be nonmonotonic reaching the minimum in structures where the scattering time is comparable to the period of spin precession in the effective magnetic field.