Observation of fluorescence in the THz frequency region from semi-insulating bulk GaAs excited by ultrashort pulses

THz radiation from various material excited by ultrashort pulse lasers have been intensively studied in the respect of its mechanism and potential application to ultrafast opto-electronics. Especially quantum well sample applied with electrical field was found out to be quite efficient. In this presentation, we will describe the observation of THz radiation not due to the rectification from semi-insulating bulk GaAs excited by ultrashort-laser pulses and its intensity dependence on the 1.5-th power of the excitation intensity.<
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