Weak antilocalization in quantum wells in tilted magnetic fields

TL;DR

This paper investigates weak antilocalization effects in InGaAs quantum wells under various magnetic field orientations, revealing spin relaxation mechanisms, and quantifying spin splittings and interface imperfections.

Contribution

It provides a comprehensive experimental and theoretical analysis of weak antilocalization in tilted magnetic fields, highlighting the role of Dresselhaus spin-orbit interaction and interface effects.

Findings

Spin dephasing due to Dresselhaus interaction

In-plane field destroys weak antilocalization

Values of g-factor and interface roughness characterized

Abstract

Weak antilocalization is studied in an InGaAs quantum well. Anomalous magnetoresistance is measured and described theoretically in fields perpendicular, tilted and parallel to the quantum well plane. Spin and phase relaxation times are found as functions of temperature and parallel field. It is demonstrated that spin dephasing is due to the Dresselhaus spin-orbit interaction. The values of electron spin splittings and spin relaxation times are found in the wide range of 2D density. Application of in-plane field is shown to destroy weak antilocalization due to competition of Zeeman and microroughness effects. Their relative contributions are separated, and the values of the in-plane electron g-factor and characteristic size of interface imperfections are found.