Dual‐Color Flexible Metasurfaces with Polarization‐Tunable Plasmons in Gold Nanorod Arrays

Abstract Optical metasurfaces have attracted growing attention in plasmonic structural color in recent years due to their supreme performance in display and imaging technologies. However, real‐life applications of optical metasurfaces so far are often hindered by their complex, expensive, and time‐consuming nanofabrication methods, as well as sophisticated optical measurement systems. Herein, a flexible metasurface filter, based on periodic gold nanorods, capable of changing the output color by simple rotation of a linear polarizer is proposed and demonstrated. This phenomenon is enabled by switching of resonance plasmons in the gold nanorods with the polarization of incident light. Subsequent rotation of the input polarizer leads to an output of two distinct colors and their combinations. Moreover, metasurfaces consisting of Au nanorods with different orientations are integrated into a single flexible substrate. Information can be therefore encoded into the orientations of Au nanorods and readily decoded with the color of the metasurface under polarized illumination of white light‐emitting diode without complex optical components.