双通道偏振复用可擦除介质型全息超表面  

Erasable Dual⁃Channel Polarization Multiplexed Dielectric Hologram Metasurface

作　　者：刘亮[1] 周绍林[1] 全海洋[2] 刘俊伯[2] 王建[2] 胡松[2] Liu Liang;Zhou Shaolin;Quan Haiyang;Liu Junbo;Wang jian;Hu Song(College of Microelectronics,South China University of Technology,Guangzhou 511442,Guangdong,China;Institute of Optics and Electronics,Chinese Academy of Sciences,Chengdu 610207,Sichuan,China)

机构地区：[1]华南理工大学微电子学院,广东广州511442 [2]中国科学院光电技术研究所,四川成都610207

出　　处：《中国激光》2023年第18期209-218,共10页Chinese Journal of Lasers

基　　金：广东省自然科学基金(2022A1515010872);广州市基础与应用基础研究(202201010110)。

摘　　要：为进一步增强加密或存储器件的实用性与安全性,设计并实现了一种多通道偏振复用的相变全息超表面,通过在多通道全息超表面设计中引入相变介质,实现了动态的可擦除功能。当耦合相变介质层处于非晶态时,所构造的编码超表面可以产生两个独立成像的全息通道。当相变介质变为晶态时,决定相位调控的交叉偏振被关闭,对应的相位编码“被擦除”。Objective Recently,emerging ultracompact planar photonic devices have been developed using a plurality of metasurfaces with excellent performance in light manipulation.In particular,the versatility of metasurfaces in pixel-level high-resolution phase control has prompted the emergence of single-channel metasurface holograms that simplify the computer-generated hologram(CGH)production procedure.Subsequently,the progressive advancement of multi-channel metasurface holograms with polarizationmultiplexed control opens a new direction for potential applications such as optical encryption and storage.However,most optical holographic or storage metasurfaces are currently static and lack mechanisms for active regulation or dynamic anticounterfeiting.In this scenario,to further strengthen the applicability and security level of optical encryption and storage devices,this study proposes a type of actively switchable or“erasable”metasurface hologram with multi-channel polarization-dependent multiplex control.Although diverse mechanisms for active control are available,such as liquid crystals,semiconductors,conductive oxides,varactors,and device architecture design based on micro-electromechanical system,the phase change materials integrating scheme transpires to be a solution with a practical trade-off owing to its advantages of nonvolatile and high-speed switching control,and a significant number of reversible phase transitions.Method In this study,by introducing the phase-change dielectrics of GeSbSeTe with almost no loss into the multi-channel holographic metasurface architecture,a type of phase-change dielectric meta-hologram concurrently with actively“erasable”control is achieved for the incidence of circularly-polarized(CP)waves.In order to achieve the two-dimensional(2D)isotropic phase encoding with“erasable”control,the GeSbSeTe elliptical pillars with varied diameters are screened out initially via a rigorous process of numerical calculations to produce a phase map that covers the full range of 0‒2π.S

关 键 词：全息 超表面全息 相变介质 双通道复用全息 几何相位 

分 类 号：O436[机械工程—光学工程]