Optical power stabilization using a germanium photodiode and a variable optical attenuator integrated on a silicon wire waveguide platform

Abstract

We have demonstrated fast optical power stabilization using a germanium photodiode and a silicon variable optical attenuator monolithically integrated on a compact silicon photonic platform. These integrated devices work synchronously with a ~100-MHz bandwidth. With an external electronic feedback circuit, the output power of the device is stabilized within an error of 3.7 dB for 20-dB input power variation. Feedback response time is about 100 ns.