Adiabatic tapered S-bends for compact digital switch arrays

摘要

An optical switch array in an MxN configuration has a set of M input digital optical Y-branches; a set of N output digital optical Y-branch; and at least one S-bend interconnect waveguide connecting at least one input digital optical Y-branch to at least one output digital optical Y-branch, with the S-bend interconnect waveguide being adiabatically tapered for providing adiabatic modal evolution between the at least one input and output digital optical Y-branches. Each of the set of N output digital optical Y-branches has an associated branch separation point; and an output port of the at least one tapered S-bend interconnect waveguide is connected substantially adjacent to a respective branch separation point of a respective one of the set of N output digital optical Y-branch. Compact digital optical switch arrays can be fabricated using such adiabatically tapered S-bend interconnects to eliminate the overlap sections of intermediate digital optical switch elements of the digital optical switch array, and thus to reduce the overall length of the digital optical switch array for providing improved propagation characteristics.