Multifrequency Acousto-Optic Diffraction in Wideband Bragg Cells

A fundamental limit for the dynamic range of acousto-optic signal processor is the intermodulation products (IMPs) generated by nonlinearities in the Bragg cells when simultaneous signals are present. For wideband Bragg cells it was found the dominant contribution of the IMPS is due to acoustic nonlinearities in the Bragg cell medium. A coupled mode analysis is presented for the nonlinear interaction of multiple acoustic waves at different c arrier frequencies. Approximate truncated s eries solutions of the dominant IMPs are derived for two signals case. Experimental results obtained with Te02 and GaP cells are presented.