A Novel Blocking State of Silicon Electro-Optical Switch Based on Free Carrier Absorption Effect

We propose and experimentally demonstrate a novel blocking state of a silicon electro-optical switch based on free carrier absorption effect. By injecting the holes and electrons into waveguides of a 2 × 2 Mach-Zehnder interferometer electro-optical switch, both outputs of the switches can be blocked at the same time. The extinction ratios of two outputs of 24-dB and 28-dB are respectively obtained for the blocking state around 1550 nm.