Dynamically reconfigurable 2D polarization-agnostic image edge-detection using nonvolatile phase-change metasurfaces.

The development of novel, compact, and reconfigurable devices for optical analog computing would pave the way for the next generation of imaging systems free from high power consumption electronics and computationally demanding processing algorithms. Recently, nonlocal metasurfaces have emerged as a powerful platform to perform analog image processing operations with low energy consumption, at the speed of light, and without the need to physically access the Fourier space, thereby providing both high computational speeds and ease of integration. However, once such devices are designed and fabricated, their effect on optical beams is fixed, constraining their performance to a singular function. Here, we show how nonlocal metasurfaces made of novel low-loss chalcogenide phase-change materials, such as SbSe, offer a degree of reconfigurability, enabling switching between certain imaging modes. Specifically, we show that switching between a two-dimensional edge-detection mode and a bright-field imaging mode, or between a two-dimensional edge-detection mode and a two-dimensional image blurring mode, is possible.