Near-bandgap ultrafast optical responses of furnace annealed arsenic-ion-implanted GaAs

Recently, a new class of photoconductors with excess-arsenic-related deep level defects, arsenic-ion-implanted (or GaAs:As⁺), has been the subject of intense study. Ultrafast carrier lifetimes, photoconductive and nonlinear optical responses were reported for as-implanted and RTA (rapid thermal annealing) annealed GaAs:As⁺. It is expected that the optimum furnace annealing will create arsenic precipitates which can enhance the performance of GaAs:As⁺ for photoconductive or nonlinear optical switching applications. The carrier dynamics of furnace-annealed GaAs:As⁺ is thus of substantial interests and is the focus of this paper