Laser diodes in piezoelectric quantum-well structures

InGaAs quantum-well laser structures grown on GaAs (111)B substrates by fitting the spontaneous emission spectra observed through a top contact window using a self-consistent solution of Poisson's and Schrodinger's equations. At room temperature at threshold the internal field is still 50% of its initial value and as a result the quasi-Fermi levels are closer to the band edges of the well than in a square well, causing significant carrier loss through the barrier/waveguide material. We determine the loss by this route to be twice that for a similar device if the internal field was completely screened. (C) 1996 American Institute of Physics.