Large-Scale and Fast Optical Circuit Switch for Coherent Detection Using Tunable Local Oscillators Formed with Wavelength Bank and Widely-Tunable Silicon Ring Filters

Abstract

We demonstrate a $1,024\times 1,024$ wavelength-routing optical switch with switching time under $18\mu \mathrm{s}$ for 256-Gb/s DP-QPSK signals. Wavelength selection at the receivers is achieved by fast widely-tunable (22nm) local oscillators formed using a wavelength bank and newly fabricated silicon ring filters having 5.3-dB fibre-to-fibre insertion loss.