Digitally controlled multiplexed silicon photonics phase shifter using heaters with integrated diodes.

We present a silicon side heater with integrated diode to provide multiplexed control of different elements in a photonic circuit based on the polarity of the driving signal. The diode introduces an asymmetric electrical response where the heater is only active under forward bias. This can be used to address multiple heaters through the same electrical electrical contacts. We demonstrate push-pull operation on a Mach-Zehnder interferometer with heaters in both arms, as well as time-multiplexed operation of multiple heaters by modulating the driving signal. We extend this work by demonstrating how pulse width modulation (PWM) and duobinary-PWM can be used to improve the linearity of the response of the phase shifters. (C) 2017 Optical Society of America under the terms of the OSA Open Access Publishing Agreement