Band-edge photoluminescence of heavily doped InxGa1-xAs1-yPy (lambda=1.2 mu m)

Band-edge photoluminescence spectra of heavily donor-doped samples of InxGa 1-xAs1-yPy (x=0.77, y=0.53) were investigated in the temperature range (77- 300) K. A theory of luminescence that takes into account fluctuations in th e band-edge potentials due to nonuniform distribution of impurities is used to calculate temperature dependences of the positions and half- widths of peaks in these spectra. Good agreement is obtained between experimental and calculated curves. For heavily doped InxGa1-xAs1-yPy samples with either p - or n-type conductivity, the peak energy of the band-edge PL is observed t o shift towards lower frequencies at low temperatures. This shift is accomp anied by broadening of the spectra and a decrease in the photoluminescence intensity compared to the analogous parameters for the spectra of undoped m aterial. Possible mechanisms for radiative recombination are analyzed. (C) 1999 American Institute of Physics. [S1063-7826(99)00308-7].