A New Metacanvas for Metamaterials

Unlike natural materials where the properties are defined by their chemical composition, metamaterials are a class of artificial materials where the functionalities and properties are achieved by designing the materials’ microstructures. Typically these metamaterials are made with photolithography of structures composed of both dielectrics and metals. Once made, these meta-structures cannot be altered; if a new function is needed, a new metamaterial needs to be made.

Profs. J. Wu and J. Yao groups demonstrate a way to break this limit and make possible metamaterials that are reconfigurable, or rewritable. Much like the etch-a-sketch toy that can write, erase and rewrite different patterns on the same screen, the authors write, erase and rewrite nearly arbitrary metamaterials patterns on the same thin film, which is termed as a “meta-canvas”. Distinct functionalities are demonstrated with the same piece of meta-canvas including optical devices to steer infrared beam, to polarize light, and to construct a holography. The principle of the meta-canvas is based on the hysteretic metal-insulator phase transition in vanadium dioxide thin films, where the metallic pattern is created in the insulating body of the film with local heating with a focused laser beam.
The work is published at Advanced Materials and is highlighted by the College of Engineering News, here.