Generalized Optical Signal Processing Based on Multioperator Metasurfaces Synthesized by Susceptibility Tensors

How might one design multioperator metasurface computers to realize multiple wave-based mathematical functions at the same time? The authors show in theory that using normal susceptibilities of a suitably engineered bianisotropic metasurface reveals much freedom to manipulate its nonlocal features, allowing a broader range of computing functionalities, particularly polarization- and angle-multiplexed optical signal processing. The proposed approach to optical signal processing overcomes substantial restrictions of previous designs, such as working with a single mathematical operation, slow responses, and most importantly supporting only the even symmetry operations for normal incidences.