Efficient generation of vectorial terahertz beams using surface-wave excited metasurfaces  

作　　者：Zhuo Wang Weikang Pan Yu He Zhiyan Zhu Xiangyu Jin Muhan Liu Shaojie Ma Qiong He Shulin Sun Lei Zhou 

机构地区：[1]State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures(Ministry of Education),Fudan University,Shanghai 200433,China [2]Shanghai Engineering Research Centre of Ultra Precision Optical Manufacturing,Department of Optical Science and Engineering,School of Information Science and Technology,Fudan University,Shanghai 200433,China [3]Shanghai Key Laboratory of Metasurfaces for Light Manipulation,Shanghai 200433,China [4]Yiwu Research Institute of Fudan University,Chengbei Road,Yiwu City 322000,China.

出　　处：《Opto-Electronic Science》2025年第1期1-11,共11页光电科学(英文)

基　　金：the financial support from National Natural Science Foundation of China (Nos. 62192771, 12374344, 12221004);National Key Research and Development Program of China (2022YFA1204700, 2020YFA0710100);Natural Science Foundation of Shanghai (Grant No. 23dz2260100);China Postdoctoral Science Foundation 2021TQ0077

摘　　要：On-chip devices for generating pre-designed vectorial optical fields(VOFs)under surface wave(SW)excitations are highly desired in integrated photonics.However,conventional devices are usually of large footprints,low efficiencies,and limited wave-control capabilities.Here,we present a generic approach to design ultra-compact on-chip devices that can efficiently generate pre-designed VOFs under SW excitations,and experimentally verify the concept in terahertz(THz)regime.We first describe how to design SW-excitation metasurfaces for generating circularly polarized complex beams,and experimentally demonstrate two meta-devices to realize directional emission and focusing of THz waves with oppo-site circular polarizations,respectively.We then establish a systematic approach to construct an integrated device via merging two carefully designed metasurfaces,which,under SW excitations,can separately produce pre-designed far-field patterns with different circular polarizations and generate target VOF based on their interference.As a proof of con-cept,we demonstrate experimentally a meta-device that can generate a radially polarized Bessel beam under SW excita-tion at~0.4 THz.Experimental results agree well with full-wave simulations,collectively verifying the performance of our device.Our study paves the road to realizing highly integrated on-chip functional THz devices,which may find many ap-plications in biological sensing,communications,displays,image multiplexing,and beyond.

关 键 词：surface waves vector beam multi-pixel metasurface TERAHERTZ ultrathin and high-efficiency 

分 类 号：TN25[电子电信—物理电子学]