Optical spectroscopy of the two-dimensional electron gas in GaxIn1-xAs/AlyIn1-yAs single quantum wells.

摘要: We report the results of a detailed photoluminescence investigation on n-type modulation-doped ${\mathrm{Ga}}_{\mathit{x}}$${\mathrm{In}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$As/${\mathrm{Al}}_{\mathit{y}}$${\mathrm{In}}_{1\mathrm{\ensuremath{-}}\mathit{y}}$As single quantum wells with intentional Be-acceptor doping in central region well. Strong collective recombinations electrons different k states up to Fermi wave vector two-dimensional electronic system and excess photogenerated holes bound ionized Be acceptors are observed. At higher sample temperatures, thermalized become free. The optical transitions then conserving. A similar effect has been observed when outnumber doped under photoexcitation densities. binding energy is determined be 12 meV basis temperature-dependent measurements.