In a study published in eLight, scientists have significantly advanced metasurface technology by creating a novel design. This design projects holographic images and produces special diffraction patterns using a quasicrystal's ten-fold rotation symmetry. The ultra-thin material merges the unique properties of quasicrystals with advanced light manipulation techniques.
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. Image Credit: Chi Xu, Ruizhe Zhao, Xue Zhang, Shifei Zhang, Xin Li, Guangzhou Geng, Junjie Li, Xiaowei Li, Yongtian Wang, Lingling Huang
Metasurfaces, renowned for their capability to manipulate light in unique ways, offer the potential for a new generation of ultra-thin devices. These applications include holographic displays, light switching, and advanced security features.
Traditionally, metasurfaces have relied on tiny structures known as meta-atoms arranged in regular grids. This new design deviates from convention by positioning these meta-atoms in a complex, quasicrystal pattern. Quasicrystals are organized but lack repetitive structures, enabling the metasurface to perform dual functions simultaneously.
The metasurface can manipulate the phase of light to recreate an image at a specific distance, effectively generating holographic displays. Additionally, the quasicrystal arrangement of meta-atoms produces unique light diffraction patterns visible in the far field.
This novel design offers substantial advantages over traditional metasurfaces. Its multifunctionality allows a single metasurface to carry out two tasks at once, streamlining device design. Moreover, the quasicrystal configuration provides enhanced precision in light manipulation. This approach, which merges the global symmetry of a metasurface with the localized response of meta-atoms, adds new functionalities.
These innovations herald a new era of ultra-thin devices with promising applications. They could lead to high-resolution, slim holographic displays suitable for various uses, ultra-fast and efficient light-switching devices, and intricately designed diffraction patterns for 3D imaging and optical security.
For instance, this technology could enhance security features, such as diffractive elements for anti-counterfeiting and secure communication. Additionally, by simultaneously monitoring the wavefront and diffraction patterns, this technology could reveal new insights into the unique properties and responses of multi-substance quasicrystals.
Journal Reference:
Xu, C., et. al. (2024) Quasicrystal metasurface for dual functionality of holography and diffraction generation. eLight. doi:10.1186/s43593-024-00065-7