Photoluminescence study of a current density filament during an impact ionization avalanche in n-GaAs

Photoluminescence (PL) spatial patterns and the PL spectra inside a current density filament have been investigated in n-GaAs at 4.2 K during impact ionization avalanche under an applied pulse voltage. The bright photoluminescence (PL)-pattern observed by applying a pulse voltage characterizes the formation of a current density filament well. The PL brightening was observed only with weak photoexcitation density (Jp≅218 μW/cm2) under the applied pulse voltage with repetition frequency of f0=8 kHz. The observations of the bright PL spectra inside the current density filament provide a relatively new result with regard to the partial Auger recombination process of the (D0,X) complex, leaving the neutral donor in the excited states.