Optical spin-symmetry breaking for high-efficiency directional helicity-multiplexed metaholograms

作     者：Muhammad Ashar Naveed Muhammad Afnan Ansari Inki Kim Trevon Badloe Joohoon Kim Dong Kyo Oh Kashif Riaz Tauseef Tauqeer Usman Younis Murtaza Saleem Muhammad Sabieh Anwar Muhammad Zubair Muhammad Qasim Mehmood Junsuk Rho Muhammad Ashar Naveed;Muhammad Afnan Ansari;Inki Kim;Trevon Badloe;Joohoon Kim;Dong Kyo Oh;Kashif Riaz;Tauseef Tauqeer;Usman Younis;Murtaza Saleem;Muhammad Sabieh Anwar;Muhammad Zubair;Muhammad Qasim Mehmood;Junsuk Rho

作者机构：NanoTech LabDepartment of Electrical EngineeringInformation Technology University(ITU)of the PunjabFerozepur RoadLahore54600Pakistan Department of Mechanical EngineeringPohang University of Science and Technology(POSTECH)Pohang37673Republic of Korea Department of PhysicsLahore University of Management Sciences(LUMS)Lahore54792Pakistan Department of Chemical EngineeringPohang University of Science and Technology(POSTECH)Pohang37673Republic of Korea National Institute of Nanomaterials and Technology(NINT)Pohang37673Republic of Korea 

出 版 物：《Microsystems & Nanoengineering》 (微系统与纳米工程（英文）)

年 卷 期：2021年第7卷第2期

页      面：71-79页

核心收录：

学科分类：070207[理学-光学] 07[理学] 08[工学] 0803[工学-光学工程] 0702[理学-物理学] 

基　　金：This work was financially supported by the LGD-SNU incubation program funded by LG Display and the National Research Foundation of Korea(NRF)grants(NRF-2019R1A2C3003129 CAMM-2019M3A6B3030637 NRF-2019R1A5A8080290)funded by the Ministry of Science and ICT(MSIT)of the Korean government.M.Q.M acknowledges a research grant by Higher Education Commission(HEC)of Pakistan through National Research Program for Universities(NRPU)[Project No.10177/Punjab/NRPU/R&D/HEC/2017]to support this work.M.Q.M. T.T. K.R. U.Y. and M.Z.acknowledge their internal research grants from ITU.M.A.A.acknowledges the Pre-Doctoral Fellowship from ITU.I.K.acknowledges the NRF Sejong Science fellowship(NRF-2021R1C1C2004291)funded by the MSIT of the Korean government 

主　　题：directional breaking visible 

摘      要：Helicity-multiplexed metasurfaces based on symmetric spin–orbit interactions (SOIs) have practical limits because they cannot provide central-symmetric holographic imaging. Asymmetric SOIs can effectively address such limitations, with several exciting applications in various fields ranging from asymmetric data inscription in communications to dual side displays in smart mobile devices. Low-loss dielectric materials provide an excellent platform for realizing such exotic phenomena efficiently. In this paper, we demonstrate an asymmetric SOI-dependent transmission-type metasurface in the visible domain using hydrogenated amorphous silicon (a-Si:H) nanoresonators. The proposed design approach is equipped with an additional degree of freedom in designing bi-directional helicity-multiplexed metasurfaces by breaking the conventional limit imposed by the symmetric SOI in half employment of metasurfaces for one circular handedness. Two on-axis, distinct wavefronts are produced with high transmission efficiencies, demonstrating the concept of asymmetric wavefront generation in two antiparallel directions. Additionally, the CMOS compatibility of a-Si:H makes it a cost-effective alternative to gallium nitride (GaN) and titanium dioxide (TiO2) for visible light. The cost-effective fabrication and simplicity of the proposed design technique provide an excellent candidate for high-efficiency, multifunctional, and chip-integrated demonstration of various phenomena.