Active broadband unidirectional focusing of terahertz surface plasmons based on a liquidcrystal-integrated on-chip metadevice  

作　　者：YI-MING WANG FEI FAN HUI-JUN ZHAO JING LIU YUN-YUN JI JIE-RONG CHENG SHENG-JIANG CHANG 

机构地区：[1]Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology,Institute of Modern Optics,Nankai University,Tianjin 300350,China [2]Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology,Tianjin 300350,China

出　　处：《Photonics Research》2024年第10期2148-2157,共10页光子学研究（英文版）

基　　金：National Natural Science Foundation of China(62205160,62235004,62335012,62371258);Fundamental Research Funds for the Central Universities(Nankai University)(63241330)。

摘　　要：Surface plasmons have been given high expectations in terahertz(THz)on-chip photonics with highly bound integrated transmission and on-chip wavefront engineering.However,most surface plasmonic coupling strategies with tailorable polarization-dependent features are challenged in broadband propagation and dynamic manipulation.In this work,a liquid crystal(LC)-integrated surface plasmonic metadevice based on arc-arrayed pair-slit resonators(APSRs)is demonstrated.The mirror-symmetry structures of this metadevice achieve the spin-selective unidirectional achromatic focusing,of which the broadband characteristic is supported by containing multiple APSRs with slits of different sizes corresponding to different excitation frequencies.Moreover,arc radii are precisely designed to meet the phase matching condition of constructive interference,so that the operating frequency of this on-chip metadevice is broadened to 0.33–0.60 THz.Furthermore,the LC integration provides the active energy distribution between the left and right focal spots,and the actual modulation depth reaches up to 73%.These THz active,wideband,on-chip manipulation mechanisms and their devices are of great significance for THz-integrated photonic communication,information processing,and highly sensitive sensing.

关 键 词：polarization UNIDIRECTIONAL crystal 

分 类 号：O441.4[理学—电磁学] O53[理学—物理]