Phase-change metasurfaces for reconfigurable image processing

Abstract

Optical metasurfaces have enabled high-speed, low-power image processing within a compact footprint. However, reconfigurable imaging in such flat devices remains a critical challenge for fully harnessing their potential in practical applications. Here, we propose and demonstrate phase-change metasurfaces capable of dynamically switching between edge-detection and bright-field imaging in the visible spectrum. This reconfigurability is achieved through engineering angular dispersion at electric and magnetic Mie-type resonances. The customized metasurface exhibits an angle-dependent transmittance profile in the amorphous state of Sb2S3 meta-atoms for efficient isotropic edge detection, and an angle-independent profile in the crystalline state for uniform bright-field imaging. The nanostructured Sb2S3-based reconfigurable image processing metasurfaces hold significant potential for applications in computer vision for autonomous driving systems.