All-optical remotely controllable 1 × 8 silicon thermo-optic switch based on Mach-Zehnder interferometers

We have proposed an all-optical switch based on a thermo-optic (TO) phase shifter with pump lights to control the on/off state of signal lights. In this study, we experimentally demonstrate the 1 × 8 Mach-Zehnder interferometer (MZI)-based silicon TO switch that performed broadband switching with the worst crosstalk of 15.2 dB in the C-band wavelength range and minimum insertion loss of 5.0 dB. Using a titanium metal heater, the elementary unit of this device, the 1 × 2 MZI-based TO switch, exhibited a π-phase-shift power P_π of 46.2 mW with switching times of 1.7 µs and 4.4 µs for 10%-90% rising time and 90%-10% falling time, respectively. Moreover, our proposed device can find applications in passive optical network systems to achieve remote control in all-optical signal processing.