X-ray diffraction from piezoelectrically amplified shear waves in the 50-GHz range

Abstract

X-ray diffraction from piezoelectrically amplified acoustic shear waves in GaAs is reported. The spectrum of amplified acoustic flux is obtained in the microscopic limit, where the electron mean free path is much greater than the acoustic wavelength. The peak acoustic intensity occurs at 50 GHz, which corresponds to the frequency of maximum net gain according to the linear theory. The spectrum of piezoelectrically amplified acoustic waves is observed at frequencies an order of magnitude larger than may be studied by the previously reported Brillouin scattering technique. © 1971 The American Institute of Physics.