PHOTOLUMINESCENCE AND MAGNETOLUMINESCENCE LINESHAPES IN DEGENERATE SEMICONDUCTOR QUANTUM-WELLS

A microscopic theory and data are presented for the low-temperature photo- and magneto-luminescence lineshape in modulation-doped quantum-wells. The luminescence linewidths arise primarily from ionized-impurity scattering of the carriers. Treating electron-hole recombinations through direct as well as impurity-assisted (indirect) processes yields good agreement to the lineshape of photoluminescence data from strained In(x)Ga1-x/GaAs quantum-wells. For magneto-luminescence, we present experimental and theoretical evidence of a new selection rule arising from impurity-assisted off-diagonal (i.e., DELTA-n not-equal 0) transitions between conduction- and valence-band Landau levels (n = 0, 1, ..).