|Authors: ||Z. Gao, X. Chen, Z. Zhang, U. Chakraborty, W. Bogaerts, D. Boning|
|Title: ||Automatic Synthesis of Light Processing Functions for Programmable Photonics: Theory and Realization|
|Format: ||International Journal|
|Publication date: ||Submitted for publication. Not yet published|
|Journal/Conference/Book: ||Photonics Research
|Citations: ||Look up on Google Scholar
Linear light processing functions (e.g., routing, splitting, filtering) are key functions requiring configuration to implement on a programmable photonic integrated circuit (PPIC). In recirculating waveguide meshes (which include loop-backs), this is usually done manually. Some previous results describe explorations to perform this task automatically, but their efficiency or applicability is still limited. In this paper, we propose an efficient method that can automatically realize configurations for many light processing functions on a square-mesh PPIC. At its heart is an automatic differentiation subroutine built upon analytical expressions of scattering matrices, which enables gradient descent optimization for functional circuit synthesis. As demonstrated in numerical results, the advantages of our method include: (i) gradients are calculated analytically instead of using numerical differentiation, making the high-dimensional optimization solvable in time scales of minutes; and (ii) our method is suited to a wide range of light processing functions, and can synthesize multiple functions on the same PPIC simultaneously.
Related Research Topics