Temporal and spatial modulations of phase of diffracted light in Raman-Nath acousto-optic diffraction

摘要

The Raman-Nath acousto-optic diffraction contains multiple diffraction orders. Each order diffracted light was still considered a plane light wave. However, we find that each order diffracted light is not a plane light wave, and that its optical phase is modulated temporally and spatially by the sound wave. Additionally, both the optical phase modulations and frequency shifts cause the temporal fluctuation of light intensity escaping from the acoustic field. At last, the optical phase modulations also cause the spatial fluctuation of light intensity escaping from the acoustic field.