Electrolyte-Gating for Metasurfaces and Large-Area Fabrication

Alternative materials for metasurfaces enable new properties and lay the foundation for advantage applications. This talk will discuss two strategies for new, tunable metasurfaces. The first part of the talk will discuss the use of electrolyte gating to control the optical properties of materials, focusing on La_1-xSr_xCoO_3-_d (LSCO) as an exemplary case. We fabricate electric double layer transistors using LSCO and an ion gel, and under application of positive gate voltage gating facilitates the formation and migration of oxygen vacancies, and a transition from a perovskite phase to an oxygen-vacancy-ordered brownmillerite phase. This is accompanied by substantial change in optical properties, as measured with spectroscopic ellipsometry. The talk will discuss how LSCO can be incorporated with metasurfaces to produce tunable optical response. The second part of the talk will discuss a new strategy for fabricating large-area metasurfaces, using roll-to-roll compatible additive manufacturing methods. This method, which uses solution-based inks to create the metasurfaces, can pattern a variety of materials, including metals, dielectrics, and semiconductor nanocrystals, and also create multilayer structures.