Multispectral metasurface for visible transparency, infrared stealth, and mm-Wave frequency-multiplexing

Metasurfaces have shown remarkable capabilities in tailoring the electromagnetic wavefronts at a subwavelength scale. However, existing metasurfaces that operate at a customized frequency still face significant challenges in satisfying the demands of multi-mode surveillance technologies and integrated systems. Here, we propose a concept of multispectral metasurface that can achieve the compatibility of visible, infrared, and millimeter-wave frequency regions, thereby not only expanding the degree of freedom in manipulating electromagnetic fields, but also facilitating the development of modern optoelectronic devices requiring miniaturization and integration. The proposed metasurface consists of two sets of meta-atoms arranged in an interleaved configuration, enabling independent 3-bit phase modulation at two distinct millimeter-wave frequencies. Proof-of-concept experiments demonstrate the implementation of a frequency-selective bifocal metalens and a dual-channel meta-hologram using the proposed design, both of which exhibit high visible transparency and low infrared emissivity simultaneously. This work provides a new paradigm for multispectral-compatible metasurfaces with boosted information capacity for various application scenarios, including optical windows, high-gain lens antennas, and wireless communication systems requiring multi-channel signal processing.