Low-power, 2x2 silicon electro-optic switch with 110-nm bandwidth for broadband reconfigurable optical networks

We present an ultra-broadband Mach-Zehnder based optical switch in silicon, electrically driven through carrier injection. Crosstalk levels lower than -17 dB are obtained for both the 'on' and 'off 'switching states over an optical bandwidth of 110nm, owing to the implementation of broadband 50% couplers. Full 2x2 switching functionality is demonstrated, with low power consumption (∼ 3 mW) and a fast switching time (< 4 ns). The utilization of standard CMOS metallization results in a low drive voltage (< 1 V) and a record-low V _πL (∼ 0.06 V·mm). The wide optical bandwidth is maintained for temperature variations up to 30K.