Comparative study of (1 0 0) and (1 1 1)B InGaAs single quantum well laser diodes

In this work, a series of identical InxGa1−xAs/AlyGa1−yAs single quantum well laser diodes, grown on (100) and View the MathML source GaAs substrates, have been thoroughly studied. For all samples, clear evidence of reduced threshold current densities in the View the MathML source substrate has been observed in electroluminescence spectra at 17 and View the MathML source. Modelling of the devices, based on a self-consistent solution of Schrödinger–Poissonʹs equations, was utilised in order to reproduce the experimental results. The model incorporates strain and piezoelectric effects on the quantum well states, free carrier screening, overlap integral computation, and optical gain calculation. The underlying mechanism, that explains the threshold reduction observed in the View the MathML source laser diodes, is discussed based on the results of the modelling.