Programmable Integrated Silicon Photonics Waveguide Meshes: Optimized Designs and Control Algorithms

Abstract

Programmable Integrated Photonics is a recent area of research that aims to integrate a very-large scale of reconfigurable photonic resources to enable flexible and versatile photonic integrated circuits. In this paper we review the state of the art of general-purpose waveguide mesh arrangements with a special focus on those that allow the synthesis of optical feedback loops. Moreover, we propose for the first time three alternative waveguide mesh topologies that decouple the performance and the geometry of previously reported architectures while achieving a higher-component density integration. This innovation is of special relevance to mitigate one of the main scalability limitations, the integration area. The paper finalizes with an introduction to control algorithms for waveguide mesh arrangements based on derivative methods and non-derivative methods. These control methods provide a proof for the self-reconfiguration of large-scale waveguide mesh arrangements. In particular, we apply the computational optimization algorithms to program an hexagonal waveguide mesh to emulate a 1x8 beamforming network and an optical filter based on an unbalanced MZI design. All in all, the paper comprises recipes to achieve truly practical softwaredefined photonic integrated circuits.

Auto-routing algorithm for field-programmable photonic gate arrays

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Photonic configurable logic block for digital photonic integrated circuits

“…The array of logic blocks are wired up by reconfigurable interconnects, allowing the chip to be programmed with either VHDL or Verilog HDL. Similarly, in the design of photonic FPGA (pFPGA), the reconfigurable photonic logic blocks (photonic configurable logic block (pCLB)) are a sea of universal photonic gates (UPGs) that can be used to perform the required logical operations in photonic way [1–7 ]. In photonics, Mach–Zehnder interferometer (MZI) is being used to perform all the logical operations [8 ].…”