Measurement of Spin-Relaxation Times by Time-Resolved Photoluminescence

Abstract

Optically pumped p-type GaAs is a most promising material for the probes of spin-polarized scanning tunneling microscopes (SP-STMs). A long spin relaxation time is an important factor in the application, and it was reported that the δ-doped GaAs/AlGaAs double heterostructure has a longer spin relaxation time than that of bulk p-type GaAs.We studied the spin relaxation process in the structure by time-correlation single-photon counting (TCPC). It was confirmed that the relaxation time strongly depends on the dopant distribution.