Polarization and Frequency Multiplexed Terahertz Meta-Holography

Seeking effective and precise control over electromagnetic waves has always been an important focus in optics. Advances in nanofabrication technology have led to designer metasurfaces, which open up new possibilities by allowing almost arbitrary spatial distributions of optical properties to be realized. This study demonstrates a multiplexed meta-hologram generating different images for different polarizations and different terahertz frequencies. By utilizing C-shape bar resonators as the basic unit cells, simultaneous binary amplitude modulation and binary phase modulation in each pixel is realized. With polarization and frequency selective independent simultaneous control of amplitude and phase in every pixel, the proposed meta-hologram makes use of all four fundamental properties of electromagnetic waves. Generation of holographic images of C, F, T, or W depending on polarization and frequency is demonstrated theoretically and experimentally. This approach, allowing for modulation of all characteristics of electromagnetic waves, paves the way for designing complex metasurfaces and meta-holograms with multiplexed functionalities, which may have applications in multichannel communication and data storage.