ИСТИНА

Integrated optics has already taken an important place in prospective areas of technology such as communication and optical modulators, optical neural networks, and quantum computing. The core device for tackling these tasks is a programmable multiport interferometer, or photonic processor, which is capable of realizing reconfigurable unitary transformations upon its optical modes. However, once a photonic processor is fabricated it should be properly calibrated for desired unitary transformation implementation, which is a separate experimental procedure that can be quite challenging for optical chips with complex interferometric structure. Here we demonstrate successful programming of a reconfigurable 4×4 photonic processor, consisting of two 4×4 directional couplers cascaded with three tunable phase shifters.