image: The demonstrated QCMs can reconstruct holographic images and display diffraction patterns simultaneously. Silicon nanofins are arranged in the Penrose tiling pattern as illustrated by the 2D color image on the surface of the quartz substrate to form the QCM. The letter “A” chosen as a holographic image is reconstructed at the predefined distance by the phase distribution of the QCM. And the far-field diffraction pattern with ten-fold rotation symmetry is generated due to the quasi-periodic array. The unit cells in the bottom right corner indicate the cyan thick rhomb and pink thin rhombs of Penrose tiling.
Credit: by Chi Xu, Ruizhe Zhao, Xue Zhang, Shifei Zhang, Xin Li, Guangzhou Geng, Junjie Li, Xiaowei Li, Yongtian Wang, Lingling Huang
Scientists have leapt forward in metasurface technology, developing a new design that simultaneously projects holographic images and creates special diffraction patterns with ten-fold rotation symmetry of quasicrystal. This ultra-thin material merges the unique properties of quasicrystals with light manipulation techniques.
Metasurfaces, already known for their ability to bend light in unusual ways, hold promise for a new generation of ultra-thin devices in areas like holographic displays, light switching, and even advanced security features.
Traditionally, metasurfaces rely on tiny structures called meta-atoms arranged in a regular grid. This new design breaks the mold by positioning these meta-atoms in a more complex, quasicrystal pattern. Quasicrystals, while ordered, lack repetitive structures. This innovative arrangement allows the metasurface to achieve two functionalities at once.
By manipulating the phase of light, the metasurface can be programmed to reconstruct an image at a specific distance, essentially generating holographic displays. Additionally, the arrangement of metaatoms in a quasicrystal pattern creates unique diffraction patterns of light visible in the far field.
This new design offers significant advantages over conventional metasurfaces. First, its multifunctional nature allows a single metasurface to perform two tasks simultaneously, simplifying device design. Second, the quasicrystal arrangement grants more precise control over light manipulation. Quasicrystal metasurfaces have unique advantages over periodic arrangements. It can be designed by combining the global symmetry of metasurface with the local response of meta-atoms. As a result, additional functionality can be achieved.
These advancements pave the way for a new generation of ultra-thin devices with exciting possibilities. High-resolution, thin holographic displays could be created for various applications. Ultra-fast and efficient light-switching devices are also within reach. Judiciously designed diffraction patterns with high-resolution holographic images could be created for 3D imaging and optical security. For example, this technology can promise advanced security features, such as diffractive elements used in anti-counterfeiting and secure communication. Furthermore, such phenomenon may provides a new perspective for revealing multi-substances of quasicrystals that possess special arrangement together with local optical response surpassing amplitude, through simultaneously detecting the wavefront and the diffraction patterns.
Journal
eLight
Article Title
Quasicrystal Metasurface for Dual Functionality of Holography and Diffraction Generation