Nonlinear behaviors of low-temperature-grown GaAs based photodetectors at long telecommunication wavelength (/spl sim/1.3 /spl mu/m)

We observed distinct nonlinear behaviors of bandwidth degradation in low-temperature-grown-GaAs based traveling-wave-photodetectors under long wavelength (/spl sim/1300 nm) operation. The disclosed unique material properties of LTG-GaAs at different excitation wavelengths are important for its applications in ultrafast optoelectronic and understanding its carrier dynamics in the defect states.