Experimental demonstration of silicon photonic devices optimized by a flexible and deterministic pixel-by-pixel technique

We present the experimental realization of photonic devices optimized by a pixel-by-pixel binary optimization method, which can straightforwardly take into account the technological constraints such as minimum feature sizes in the fabrication process. In this approach, for each iteration, one considers all the candidate structures that differ by a single pixel from the starting structure and update by adopting the structure that has the best figure of merit among all candidate structures. This approach can be implemented with high computational efficiency using a Green's function method. The devices optimized by this approach have been realized on 200 mm and 300 mm Silicon-On-Insulator platforms, using either e-beam lithography or deep-UV immersion lithography. Characterizations experimentally demonstrate the reliability of the method, given the technological constraints of Silicon Photonics.