Electron Spin Relaxations in the Electric-Field Applied GaAs/InGaAs Heterostructure

摘要

We have investigated the electron spin relaxation rates in GaAs/InGaAs heterostructure in the presence of electric field by time-resolved photoluminescence (PL) measurements at 10 K. Spin-polarized electrons were optically generated in the bulk GaAs region, drifted driven by the electric field, and captured in two InGaAs quantum wells which work as spin detectors. The comparison of the degrees of PL polarizations from two wells, by adjusting excitation energy and electric field, enables us to investigate the electron spin relaxation rates in the different parts of the sample separately. We have found that the spin relaxation during the drift transport in the bulk region is accelerated in the high electric fields and that a significant spin relaxation takes place when electrons are captured into the quantum well.