Hot electron dynamics study by terahertz radiation from large aperture GaAsphyphen;ihyphen;ndiodes

摘要

Subpicosecond electromagnetic pulses having tetrahertz (THz) bandwidths have been generated from large aperture GaAsphyphen;ihyphen;ndiodes under bias by illumination with femtosecond optical pulses. The amplitude and shape of the radiated pulses change with the applied bias and the wavelength of the optical pulses illuminating thephyphen;ihyphen;ndiode. Comparing this radiation with THz radiation from large aperture Siphyphen;ihyphen;ndiodes provides evidence of velocity overshoot in the transient response of optically injected electrons in GaAs.