Cylindrical vector beams reveal radiationless anapole condition in a resonant state  

作　　者：Yudong Lu Yi Xu Xu Ouyang Mingcong Xian Yaoyu Cao Kai Chen Xiangping Li 

机构地区：[1]Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications,Institute of Photonics Technology,Jinan University,Guangzhou 510632,China [2]Department of Electronic Engineering,College of Information Science and Technology,Jinan University,Guangzhou 510632,China

出　　处：《Opto-Electronic Advances》2022年第4期69-75,共7页光电进展（英文）

基　　金：financial support from the National Key R&D Program of China (YS2018YFB110012);National Natural Science Foundation of China (NSFC) (Grant Nos. 11674130, 91750110, 61522504 and 61975067);Guangdong Provincial Innovation and Entrepreneurship Project (Grant 2016ZT06D081);Natural Science Foundation of Guangdong Province, China (Grant Nos. 2016A030306016, 2016TQ03X981 and 2016A030308010);Pearl River Nova Program of Guangzhou (No. 201806010040)

摘　　要：Nonscattering optical anapole condition is corresponding to the excitation of radiationless field distributions in open resonators,which offers new degrees of freedom for tailoring light-matter interaction.Conventional mechanisms for achieving such a condition relies on sophisticated manipulation of electromagnetic multipolar moments of all orders to guarantee superpositions of suppressed moment strengths at the same wavelength.In contrast,here we report on the excitation of optical radiationless anapole hidden in a resonant state of a Si nanoparticle utilizing a tightly focused radially polarized(RP)beam.The coexistence of magnetic resonant state and anapole condition at the same wavelength further enables the triggering of resonant state by a tightly focused azimuthally polarized(AP)beam whose corresponding electric multipole coefficient could be zero.As a result,high contrast inter-transition between radiationless anapole condition and ideal magnetic resonant scattering can be achieved experimentally in visible spectrum.The proposed mechanism is general which can be realized in different types of nanostructures.Our results showcase that the unique combination of structured light and structured Mie resonances could provide new degrees of freedom for tailoring light-matter interaction,which might shed new light on functional meta-optics.

关 键 词：apole multipole decomposition all-dielectric nanoparticles 

分 类 号：O469[理学—凝聚态物理]