Abstract
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.
Highlights
Heaters are an attractive solution for phase shifting in silicon photonics due to their simplicity of implementation and compactness, compared to alternatives such as free-carrier modulators [1,2,3,4]
We present an alternative to obtain a linear response from the phase shifters by digitally driving them using a pulse width modulation (PWM) signal instead of a direct current (DC) signal
We show the spectrum profile of the Mach-Zehnder Interferometer (MZI) in inactive state. Using this as a reference, we can show that driving the heaters with a DC signal will induce a shift in the spectral response of the MZI, and the direction of the shift depends on the polarity of the DC signal
Summary
Heaters are an attractive solution for phase shifting in silicon photonics due to their simplicity of implementation and compactness, compared to alternatives such as free-carrier modulators [1,2,3,4]. If we place two such diode-loaded heaters in parallel and connect the cathode of one heater to the anode of the other, and vice versa [Fig. 2(c)], we can use a single pair of contact pads to drive either one heater of the other, depending on the polarity of the applied voltage. This scheme can be further explored by driving the device with a variable signal over time instead of a direct current (DC) voltage. This approach delivers a much more linear phase shift response in function of the driving parameter, in this case the duty cycle of the PWM
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
