Spectrum control of THz radiation from InSb surface by composite contribution of displacement current and difference frequency mixing

Summary form only given.Terahertz radiation from semiconductor surfaces irradiated with ultrashort optical pulses has been intensively studied as a novel radiation source. We observed the change of the THz radiation spectrum from InSb dependent on the azimuthal angle. The change of the spectra can be due to the interference of the THz radiation caused by the displacement current and by the difference frequency mixing. This effect can be used for controlling the THz radiation spectrum.