Photoluminescence in strained InGaAs/GaAs superlattices

We present measurements and analysis of high-quality photoluminescence (PL) data from strained In0.13Ga0.87As quantum wells confined by unstrained GaAs barriers. Data were obtained from low temperature to room temperature on peak positions, intensities, and linewidth. The latter exhibits an unusual minimum at 31 K consistent with defect binding of excitons and one monolayer fluctuations in well size. The high-temperature linewidth agrees with that expected for phonon scattering. Peak positions show excellent agreement with a Kronig–Penny model augmented by a variational calculation of the n=1 bound-state energy of the heavy-hole exciton.