Nonlocal Metasurfaces Performing Analog Mathematical Operations

摘要

Metasurfaces enable unusual manipulation of the impinging electromagnetic wavefront over a subwavelength thickness. One interesting opportunity that has been recently explored consists in the possibility of performing mathematical operations in the analog domain, with clear advantages in terms of speed and power consumption compared to digital approaches, and a footprint much smaller than classical analog computing approaches based on Fourier optics. In this context, multilayer structures and photonic crystals have been proposed in recent years, however, they are limited to narrow angular spectra or require exceptional material parameters, hence they are difficult to achieve in practice. Here, we propose a novel class of metasurfaces with a strong nonlocal response that can be engineered to realize various types of mathematical operations, including 1