Parallel Optical Computing Based on MIMO Metasurface Processors with Asymmetric Optical Response

Abstract

We present a polarization-insensitive metasurface processor to perform spatial asymmetric filtering of an incident optical beam, thereby allowing for real-time parallel optical processing. To enable massive parallel processing, we introduce a novel Multi Input-Multi Output (MIMO) computational metasurface with an asymmetric optical response that can perform spatial differentiation on two distinct input signals regardless of their polarization. In our scenario, two distinct signals set in x and y directions, parallel and perpendicular to the incident plane, illuminate simultaneously the metasurface processor, and the resulting differentiated signals are separated from each other via appropriate Spatial Low Pass Filters (SLPF). By leveraging Generalized Sheet Transition Conditions (GSTCs) and surface susceptibility tensors, we design an asymmetric meta-atom augmented with normal susceptibilitiesto reach asymmetric optical response at normal beam illumination. Proof-of-principle simulations are also reported along with the successful realization of signal processing functions. The proposed metasurface overcomes major shortcomings imposed by previous studies such as large architectures arising from the need of additional subblocks, slow responses, and most importantly, supporting only a single input with a given polarization. Our results set the path for future developments of material-based analog computing using efficient and easy-to-fabricate MIMO processors for compact, fast, and integrable computing elements without any Fourier lens.

arXiv comment8 pages, 8 figures

References in corpus (15)

• Double-slit photoelectron interference in strong-field ionization of the neon dimer
• Dielectric Metasurfaces for Complete Control of Phase and Polarization with Subwavelength Spatial Resolution and High Transmission
• Generalized spatial differentiation from spin Hall effect of light
• A Photonic Crystal Slab Laplace Differentiator
• High-index dielectric metasurfaces performing mathematical operations
• Digital Metasurface Based on Graphene: An Application to Beam Steering in Terahertz Plasmonic Antennas
• Analog computing by Brewster effect
• Reprogrammable Graphene-based Metasurface Mirror with Adaptive Focal Point for THz Imaging
• Generalized Optical Signal Processing Based on Multi-Operator Metasurfaces Synthesized by Susceptibility Tensors
• Spatial Integration by a Dielectric Slab Waveguide and its Planar Graphene-based Counterpart
• Analog Optical Computing by Half-Wavelength Slabs
• Self-biased Tri-state Power-Multiplexed Digital Metasurface Operating at Microwave Frequencies
• Spatial Wave Control Using a Self-biased Nonlinear Metasurface at Microwave Frequencies
• Collimating cylindrical Surface Leaky Waves for Highly Improved Radiation Characteristics of Holograms
• Asymmetric Metal-dielectric Meta-cylinders and their Potential Applications from Engineering Scattering Patterns to Spatial Optical Signal Processing

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