Organic Metasurfaces with Contrasting Conducting Polymers.

Abstract

Conducting polymers have emerged as promising active materials for metasurfaces due to their electrically tunable states and large refractive index modulation. However, existing approaches are often limited to infrared operation or single-polymer systems, restricting their versatility. In this Letter, we present organic metasurfaces featuring dual conducting polymers, polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT), to achieve contrasting dynamic optical responses at visible frequencies. Sequential electrochemical polymerizations locally conjugate subwavelength-thin layers of PANI and PEDOT onto preselected gold nanorods, creating electro-plasmonic antennas with distinct optoelectronic properties. This dual-polymer approach enables dynamic metasurface pixel control without individual electrode routing, thereby simplifying active metasurface designs. The metasurfaces exhibit dual-channel functions, including anomalous transmission and holography, through the redox-state switching of both polymers. Our work underscores the potential of conducting polymers for active metasurface applications, offering a pathway to advanced reconfigurable optical devices at visible frequencies.