Raman and photoluminescence studies of transitions of quantum‐confined acceptors

Abstract

AbstractThe internal transitions of Be acceptors confined in the center of GaAs/AlAs multiple quantum wells are investigated by Raman and photoluminescence (PL) spectra. A series of Be δ‐doped GaAs/AlAs multiple quantum wells with doping at the well center and well widths ranging from 30 to 200 Å were grown on (100) GaAs substrates by molecular beam epitaxy. Both the Raman and PL spectra were measured at 4 and 20 K, respectively. The confined longitudinal optical (LO) modes, and transitions of Be acceptors from the 1S3/2(Γ6) ground state to 2S3/2(Γ6) first excited state were clearly observed in Raman spectra. Two‐hole transitions of the acceptor‐bound excitons from the 1S3/2(Γ6) ground state to the 2S3/2(Γ6) first excited state were also observed. It is found that the experimental results in the Raman spectra are close to those measured in the PL experiments.