Programmable Metasurfaces: Advanced Optical Programming of Individual Meta‐Atoms Beyond the Effective Medium Approach (Adv. Mater. 29/2019)

In article number 1901033, Andreas Heßler, Thomas Taubner, and co-workers introduce the concept of advanced optical addressing of a metasurface covered with a phase-change material. The size, position, and crystallization depth of the switched phase-change material can be controlled using a red laser beam, leading to controlled resonance tuning for each individual meta-atom. By modifying the optical properties locally, the amplitude and phase of the light can be programmed at the meta-atom scale, enabling small adaptive corrections or multiple complex functionalities on the same metasurface.