Harmonic information transitions of spatiotemporal metasurfaces

Abstract

Metamaterials: Heightened harmonics from moving metasurfaces The generation of light harmonics by rapidly-changing metasurfaces could provide exciting new methods of information processing. Metasurfaces made from metal or semiconducting nanostructures have opened up new ways of manipulating electromagnetic waves, but most are static in nature. More recently, spatiotemporal metasurfaces have emerged, in which the ‘meta-atoms’ that affect the waves can be rearranged periodically, through electrical or mechanical forcing. Now, Tie Jun Cui and co-workers at Southeast University in Nanjing and Peking University in Beijing have explained how several useful information transitions can be induced by spatiotemporal metasurfaces. Through a theoretical model and a proof-of-principle demonstration with microwaves, the researchers show how spatiotemporal metasurfaces can generate multiple harmonics from incoming waves. These harmonics represent processed information that could benefit new technologies such as intelligent computational imaging and sixth-generation (6G) wireless networks.