Spectrally resolved detection of mixed acoustic vibrations by photorefractive interferometry

Abstract

A two-wave mixing photorefractive interferometry method in an anisotropic diffraction scheme, intended to selectively detect an acoustic vibration component at a specific frequency of interest in the presence of strong vibrations at other frequencies, is presented and validated by simulations and experiments. The achieved narrow-band detection is of particular interest for applications where weak vibration signals generated by nonlinear acoustic effects are to be detected with high sensitivity and without cross-talk from the large vibration components from which the acoustic nonlinearity is originating.