Integrated electronic controller for dynamic self-configuration of photonic circuits

TL;DR

This paper introduces a scalable electronic ASIC controller for reconfigurable photonic circuits, enabling real-time adaptive functionalities like beam coupling and signal transmission with low power and high complexity.

Contribution

The paper presents a novel ASIC design that independently controls multiple PIC elements, demonstrating scalable, real-time reconfiguration of complex photonic systems.

Findings

Successful real-time reconfiguration of a 16-channel silicon photonics device

Automatic beam coupling and wavefront distortion compensation

Transmission of 50 Gbit/s signals through free-space link

Abstract

Reconfigurable photonic integrated circuits (PICs) can implement arbitrary operations and signal processing functionalities directly in the optical domain. Run-time configuration of these circuits requires an electronic control layer to adjust the working point of their building elements and make them compensate for thermal drifts or degradations of the input signal. As the advancement of photonic foundries enables the fabrication of chips of increasing complexity, developing scalable electronic controllers becomes crucial for the operation of complex PICs. In this paper, we present an electronic application-specific integrated circuit (ASIC) designed for reconfiguration of PICs featuring numerous tuneable elements. Each channel of the ASIC controller independently addresses one optical component of the PIC, as multiple parallel local feedback loops are operated to achieve full control. The proposed design is validated through real-time reconfiguration of a 16-channel silicon photonics adaptive beam coupler. Results demonstrate automatic coupling of an arbitrary input beam to a single-mode waveguide, dynamic compensation of beam wavefront distortions and successful transmission of a 50 Gbit/s signal through an optical free-space link. The low power consumption and compactness of the electronic chip provide a scalable paradigm that can be seamlessly extended to larger photonic architectures.