Planar realization of all-optical multi-layer switching fabrics

Multi-layer switching architectures, where the layers and the parallel waveguides form N-gon prisms (N is the number of waveguides), represent a novel class of all-optical switches which (1) approach shuffle results through their 2*2-switches are interconnected in a nearest-neighbor manner and moreover (2) improve shuffle results by increasing the connectivity ( identical to number of 2*2-switches) between the prisms. However, as multi-layer switches may be difficult to implement by the current technology of photonics, the paper provides a first step towards the planar realization of this class of multi-layer switches.