Spin relaxation time dependence on optical pumping intensity in GaAs:Mn

Abstract

We analyze the dependence of electron spin relaxation time on optical pumping intensity in a partially compensated acceptor semiconductor GaAs:Mn using analytic solutions for the kinetic equations of the charge carrier concentrations. Our results are applied to previous experimental data of spin-relaxation time vs. excitation power for magnetic concentrations of approximately 1017 cm−3. The agreement of our analytic solutions with the experimental data supports the mechanism of the earlier-reported atypically long electron-spin relaxation time in the magnetic semiconductor.

Calculation of impurity density and electron-spin relaxation times in p-type GaAs:Mn

“…This method involves the analytical calculation of the concentrations of deep and shallow impurity concentrations and and respectively, using the charge neutrality condition for a partially-compensated acceptor semiconductor, as well as the consequential fitting of a plot of the dependences of spin relaxation times on excitation power for 3D and 2D ptype GaAs based on the experimental measurements of the long-spin relaxation time in the 3D material. The result reveals the best long-spin relaxation time of 77 ns for the quantum well, which is less than twice the atypically long-spin relaxation time in the 3D p-type GaAs:Mn 10 .…”