Visible-frequency nonvolatile reconfigurable Janus metasurfaces for dual-wavelength-switched and spin-asymmetric holograms  

作　　者：HUAN YUAN ZHEQIANG ZHONG BIN ZHANG 

机构地区：[1]College of Electronics and Information Engineering,Sichuan University,Chengdu 610064,China [2]Big Data Analysis and Fusion Application Technology Engineering Laboratory of Sichuan Province,Chengdu 610065,China

出　　处：《Photonics Research》2024年第2期356-368,共13页光子学研究（英文版）

基　　金：National Natural Science Foundation of China(61905167);National Key Research and Development Program of China(2020YFA0714001)。

摘　　要：Janus metasurface holography with asymmetric transmission characteristics provides new degrees of freedom for multiplexing technologies.However,earlier metasurfaces with asymmetrical transmission faced limitations in terms of tunability and multifunctionality.In this study,we propose a metasurface color holographic encryption scheme with dynamic switching and asymmetric transmission at visible frequencies using a low-loss nonvolatile optical phase-change material,Sb_(2)S_(3).Using a modified holographic optimization strategy,we achieved highfidelity asymmetric holographic imaging of a nanostructured metasurface.By controlling the incident direction and wavelength of visible light,as well as the level of crystallization of Sb_(2)S_(3),this reconfigurable metasurface enables the precise manipulation of tunable color holographic image displays.In particular,in the semi-crystalline state of Sb_(2)S_(3),the encoded information can be securely encrypted using a two-channel color-holographic image,whereas only a preset camouflaged image is displayed in the crystalline or amorphous state of Sb_(2)S_(3).The proposed multiencrypted Janus metasurface provides a potential approach for dynamic holographic displays with ultrahigh capacity,holographic encryption,and information storage.

关 键 词：holographic ASYMMETRIC VISIBLE 

分 类 号：O43[机械工程—光学工程]