Dynamic metasurfaces via reversible metal electrodeposition

Electrochemistry is a powerful approach to generate considerable optical property changes for active metasurfaces with high efficiency and signal-to-noise ratio. In particular, faradic processes that involve ions to balance the electrostatic charge can induce phase transformation in a volumetric, reversible, and non-volatile manner. However, the ion transport in redox (faradaic) reactions is inherently slower than electrostatic gating, and the potential-dependent phase transformations also comprise a tremendous amount of materials science questions at the atomic/molecular level, which invites a co-design using both materials chemistry and optical metasurface engineering. In this talk, I will introduce our research group's recent progress of active metasurfaces by reversible metal electrodeposition. The electrodeposited metal serves as the switch of cavity resonance and can enable devices with high-efficiency reflective beam steering metasurface, selective thermal emissivity, and multispectral tunability.