Nonblocking N×N integrated photonic switching architecture using rearrangeable nested rings

We report on a new N×N nonblocking integrated photonic switching architecture based on the novel method of nested rings. In comparison with other architectures, this new architecture shows various advantages such as reduction of the number of switching elements, maintenance of constant low-path difference loss, application of optical feedback, multidirectional port extension for monolithic integration, reduction of waveguide crossovers, and efficient use of the device area for ultracompact integrated switching networks.