INFRARED WAVELENGTH AND TEMPERATURE-DEPENDENCE OF OPTICALLY INDUCED TERAHERTZ RADIATION FROM INSB

Results of the temperature and infrared wavelength (0.8, 1.4, and 1.9 mum) dependence of terahertz radiation generated from both undoped and Te-doped InSb irradiated with almost-equal-to 125 fs laser pulses are reported. Undoped InSb shows a substantial change in the spectral con tent of the terahertz radiation between 80 and 260 K, while the spectr um of Te-doped InSb remains nearly unchanged, an effect attributed to its mobility being dominated by impurity scattering. Also, the teraher tz radiation from undoped InSb at 80 K is dependent on the irradiating wavelength, with both a higher frequency spectrum and much larger amp litude generated at longer wavelengths. No such effect is observed at 260 K. (C) 1994 American Institute of Physics.