Photoluminescence Study of Type I and Type II GaAs/GaP Strained-Layer Superlattices Grown on GaAs Substrates

Abstract
We studied the photoluminescence emission from short-period GaAs-GaP strained-layer superlattices grown by Atomic Layer Molecular Beam Epitaxy (ALMBE) on GaAs substrates. The observed peaks as functions of the temperature, excitation power and design parameters (period and strain accommodated in the constituent layers) were studied. Amongst the samples under study we found spatially direct (type I) and indirect (type II) superlattices. Good agreement between experiments and calculations were found for a conduction-band offset of 0.4 eV.