Electro-optic modulator for high resolution Brillouin scattering measurements

A wide band electro-optic modulator is presented which allows the frequency calibration of Brillouin spectra over the frequency range from a few MHz up to approximate to 40 GHz, a range spanning Brillouin light scattering from condensed matter. Measurements of both frequency and the linewidth of Brillouin peaks relative to longitudinal acoustic modes of water using the electro-optic modulator as a frequency reference are presented. (C) 2001 American Institute of Physics.