Sequential Monitoring and Control of a Silicon Photonic Coherent Beam Adder and Analyzer

TL;DR

This paper presents a silicon photonic circuit capable of real-time coherent beam addition and analysis, integrating reconfigurable interferometers with electronic control for scalable optical communication and sensing applications.

Contribution

It introduces a multi-aperture programmable silicon photonic circuit with integrated electronic control for simultaneous beam processing and sensing, enabling scalable and active stabilization.

Findings

Successfully demonstrated high-speed data reception at 25 Gbit/s.

Achieved real-time phase difference measurement between input beams.

Validated operation in communication and sensing scenarios.

Abstract

Joint communication and sensing applications require devices that can analyze multiple electromagnetic waves and process them in real time directly in the analog domain. In optics, the growing maturity of photonic integrated platforms allows the fabrication of complex circuits that can perform such operations, but their large number of sensors and actuators requires scalable control strategies to efficiently monitor and actively stabilize their functionality at runtime. In this work, we report on a multi-aperture silicon photonic programmable circuit that operates both as a coherent beam adder and a multi-aperture beam analyzer. The circuit consists of a reconfigurable mesh of Mach-Zehnder interferometers controlled through monolithically integrated electronic circuits, which are used to serialize/deserialize the readout of integrated sensors and the driving of actuators with a time-multiplexed addressing scheme. The circuit operation is validated in a communication and sensing scenario, where the photonic chip is used to simultaneously receive a 25 Gbit/s high-speed transmission and to measure the phase difference between the input light beams.