“Programmable” optical circuits are today the new frontier of integrated photonics and their potential has been published by the prestigious journal Nature in a study by profs. Andrea Melloni and Francesco Morichetti of DEIB – Politecnico di Milano together with the Università di Stanford, the Max Planck Institute, the Massachusetts Institute of Technology, the Università di Ghent and the Università Politecnica di Valencia.
Photonics is becoming pervasive in many application contexts and it is now necessary to have "general purpose" optical circuits programmable directly by the end user. In other words, this means borrowing the concept of electronic FPGAs (field programmable gate arrays), circuits programmable directly by the end user, which are opposed to ASIC circuits (application specific integrated circuits) designed to perform a single function.
Already three years ago, the DEIB group of Photonic Devices had perceived this potential by realizing a prototype of silicon photonic programmable optical device capable of separating strongly mixed light beams (see Sbrogliare matasse di luce: il Politecnico di Milano inventa un dispositivo che rivoluzionerà la fotonica). These same circuits can also be used to do much more, for example perform mathematical operations (such as multiplication of matrices) extremely fast, implement artificial intelligence and machine learning systems, create on-chip sensor networks and imaging systems, manipulate quantum states of light.
DEIB collaborates in this research activity with the Photonic Devices Lab, under the guidance of profs. Francesco Morichetti and Andrea Melloni and Polifab, the center of micro and nanotechnologies of the Politecnico di Milano. The activity is funded by the European H2020 Superpixels project, which aims to create next-generation sensor and imaging systems by exploiting the on-chip manipulation of light signals.
Link of the article: https://www.nature.com/articles/s41586-020-2764-0