Electro‐Active Metasurfaces Controlling Exceptional Topological Phase Through Low‐Voltage Operation on Conductive Polymer
Jaekyung Kim, Minsu Jeong, Chunghwan Jung, Junhwa Seong, Junsuk Rho
Abstract
Abstract Metasurfaces have been actively studied for their compact form factor and multifunctionality. However, their limited number of channels and lack of active modulation significantly constrain practical applications. To address these drawbacks, this study investigates electro‐active chiral optical response (EACOR)‐driven metasurfaces with dual channels, fast electrical switching rates of 52 ms, and a low operating voltage of 0.5 V. The EACOR‐driven dual‐channel metasurfaces utilize a reflective‐type metal‐insulator‐metal (MIM) structure integrated with a thin polyaniline (PANI) film as an insulator layer and chiral gold (Au) nanostructures as meta‐atoms. The chiral Au meta‐atoms exhibit a chiral optical response, creating a channel based on the polarization of the incident light. Additionally, the refractive index change of the PANI in response to the applied voltage induces variation in the chiral optical response of the proposed structure, making another channel controlled by the applied voltage. For concept validation, an electrically controlled dual‐channel metahologram is demonstrated. Such dual‐channel metasurfaces driven with a low operating voltage open a new pathway for optical encryption and display applications.