Asymmetrical photonic spin Hall effect based on dielectric metasurfaces  

作　　者：Guangzhou Geng Ruhao Pan Wei Zhu Junjie Li 耿广州;潘如豪;朱维;李俊杰(Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;School of Electronic and Electrical Engineering,Wuhan Textile University,Wuhan 430200,China)

机构地区：[1]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [2]School of Electronic and Electrical Engineering,Wuhan Textile University,Wuhan 430200,China

出　　处：《Chinese Physics B》2022年第12期267-271,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.12074420,U21A20140,and 61905274);the Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park(Grant No.Z211100004821009);the Chinese Academy of Sciences through the Project for Young Scientists in Basic Research(Grant No.YSBR-021);the Synergic Extreme Condition User Facility

摘　　要：The photonic spin Hall effect has attracted considerable research interest due to its potential applications in spincontrolled nanophotonic devices.However,realization of the asymmetrical photonic spin Hall effect with a single optical element is still a challenge due to the conjugation of the Pancharatnam-Berry phase,which reduces the flexibility in various applications.Here,we demonstrate an asymmetrical spin-dependent beam splitter based on a single-layer dielectric metasurface exhibiting strong and controllable optical response.The metasurface consists of an array of dielectric nanofins,where both varying rotation angles and feature sizes of the unit cells are utilized to create high-efficiency dielectric metasurfaces,which enables to break the conjugated characteristic of phase gradient.Thanks to the superiority of the phase modulation ability,when the fabricated metasurface is under normal incidence with a wavelength of 1550 nm,the lefthanded circular polarization(LCP)light exhibits an anomalous refraction angle of 28.9°,while the right-handed circular polarization(RCP)light transmits directly.The method we proposed can be used for the flexible manipulation of spin photons and has potentials in high efficiency metasurfaces with versatile functionalities,especially with metasurfaces in a compact space.

关 键 词：dielectric metasurface photonic spin Hall effect asymmetrical optical response 

分 类 号：O469[理学—凝聚态物理]