Parallel Optical Spatial Signal Processing Based on 2x2 MIMO Computational Metasurface

We introduce a novel concept of Multi-Input Multi-Output (MIMO) metasurface processor with asymmetric Optical Transfer Function (OTF) which can perform spatial first-order derivation on two orthogonal distinct input signals for both TM and TE polarizations. Two distinct input signals, regardless of their polarization, simultaneously illuminate the metasurface computer and the resulting differentiated signals are separated from each other via appropriate Spatial Low Pass Filters (SLPF). Our simulations confirm the claim of a 2x2 MIMO optical differentiator processor. The proposed metasurface computer is away from the restrictions such as lack of computing speed, large size of bulky or two additional sub-blocks, supporting only a single input, and constant polarization mode. Our proposed scheme pave the way for real-time massive parallel signal processing by single metasurface.