Long-lived spin memory in Mn-doped GaAs: Time resolved study

TL;DR

This study investigates electron spin dynamics in Mn-doped GaAs, revealing long spin relaxation times up to microseconds due to magnetic field effects, with implications for spintronic applications.

Contribution

It provides the first detailed measurement of long-lived electron spin relaxation times in Mn-doped GaAs using time-resolved techniques.

Findings

Electron spin relaxation time of 20 ns in transverse fields.

Extension of relaxation time to microseconds in weak longitudinal fields.

Suppression of Bir-Aronov-Pikus relaxation mechanism by magnetic fields.

Abstract

We study the electron spin dynamics in p-type GaAs doped with magnetic Mn acceptors by means of time-resolved pump-probe and photoluminescence techniques. Measurements in transverse magnetic fields show a long spin relaxation time of 20 ns that can be uniquely related to electrons. Application of weak longitudinal magnetic fields above 100 mT extends the spin relaxation times up to microseconds which is explained by suppression of the Bir-Aronov-Pikus spin relaxation for the electron on the Mn acceptor.