Acousto-optic photonic crossbar switch. Part I: design.

We present the design of a 12 × 12 photonic crossbar interconnection network constructed using a single three-dimensional acousto-optic crystal. Previous crossbars based on bulk acousto-optic cells require multichannel deflectors with one deflector per optical input; in contrast the design presented here angularly multiplexes these independent deflectors into a single-transducer acousto-optic device. A Fourier-optics analysis of an acoustically lossy Bragg deflector is coupled to a momentum-space analysis that permits the derivation of complete design equations for the switch. As a concrete example, the complete design of a 12 × 12 crossbar is presented. Finally, a coupled-mode analysis of the first- and second-order diffractions in the angularly multiplexed Bragg cell reveals the fundamental efficiency bounds of the switching network.