Piezoelectric effects in InGaAs quantum well lasers grown on (111)B GaAs substrates

High indium content InGaAs/GaAs laser structures have been grown on (111)B GaAs substrates by Molecular Beam Epitaxy (MBE). The laser devices showed room temperature CW emission, low threshold current densities and emission wavelength up to 1100 nm. The influence of the internal piezoelectric field on the emission properties is studied theoretical and experimentally. A self consistent model was developed in order to simulate the gain and spontaneous emission spectra. Modeling results were compared with measurements of the spontaneous emission spectra, and a good qualitative agreement was obtained. By analyzing these results, we conclude that the piezoelectric field is not completely screened out even for high injection currents, and that the screening level is strongly dependent on the In content. Spontaneous emission measurements in two different configurations (top and edge emission) were compared, yielding similar results for a range of experimental conditions.