J. Mangeney et al., Subgap optical absorption and recombination center efficiency in bulk GaAsirradiated by light or heavy ions, APPL PHYS L, 76(1), 2000, pp. 40-42
This letter reports the results of a comparative study on heavy- and light-
ion-irradiated semiconductors for fast saturable absorbers. The linear abso
rption of bulk GaAs irradiated either by Au+ ions or protons was measured o
ver a wide range of wavelengths below the gap. Good correspondence was foun
d between the absorption measurements and the calculated elementary defect
concentrations. Defect clustering is evidenced in the heavy-ion case. Pump-
probe experiments were used to measure the time-resolved absorption variati
ons for weakly irradiated GaAs samples under intense illumination. Much sho
rter carrier recombination times are estimated for the heavy-ion case. (C)
2000 American Institute of Physics. [S0003-6951(00)00301-6].