Stable Fano-like plasmonic resonance: its impact on the reversal of far-and near-field optical binding force  

作　　者：Hamim Mahmud Rivy M R C Mahdy Nabila Masud Ziaur Rahman Jony Saikat Chandra Das 

机构地区：[1]Department of Electrical&Computer Engineering,North South University,Bashundhara,Dhaka,1229,Bangladesh [2]School of Electrical and Electronic Engineering,Nanyang Technological University,50 Nanyang Ave,639798 Singapore [3]Pi Labs Bangladesh LTD,ARA Bhaban,39,Kazi Nazrul Islam Avenue,Kawran Bazar,Dhaka 1215,Bangladesh

出　　处：《Communications in Theoretical Physics》2020年第4期89-105,共17页理论物理通讯（英文版）

基　　金：the support of the internal grant of North South University 2018–19 and 2019–20(approved by the members of BOT,North South University,Bangladesh)along with the support of a TWAS international grant 2018–19(18-121 RG/PHYS/AS_I).

摘　　要：Even for a 100 nm interparticle distance or a small change in particle shape,optical Fano-like plasmonic resonance mode usually vanishes completely.It would be remarkable if stable Fano-like resonance could somehow be achieved in distinctly shaped nanoparticles for more than 1μm interparticle distance,which corresponds to the far electromagnetic field region.If such far-field Fano-like plasmonic resonance can be achieved,controlling the reversal of the far-field binding force can be attained,like the currently reported reversals for near-field cases.In this work,we have proposed an optical set-up to achieve such a robust and stable Fano-like plasmonic resonance,and comparatively studied its remarkable impact on controlling the reversal of near-and far-field optical binding forces.In our proposed set-up,the distinctly shaped plasmonic tetramers are half immersed(i.e.air-benzene)in an inhomogeneous dielectric interface and illuminated by?circular?polarized light.We have demonstrated significant differences between near-and far-field optical binding forces along with the Lorentz force field,which partially depends on the object’s shape.A clear connection is shown between the far-field binding force and the resonant modes,along with a generic mechanism to achieve controllable Fano-like plasmonic resonance and the reversal of the optical binding force in both far-and near-field configurations.

关 键 词：Fano resonance OPTICAL binding FORCE LORENTZ FORCE plasmonic TETRAMER 

分 类 号：O53[理学—等离子体物理]