Anomalous plasmon coupling and Fano resonance under structured light

Yang，Da Jie1,2; Im，Song Jin3; Huang，Hai Wen1; Ri，Chol Song3; Kim，Kum Dong3; Song，Kil Song3; Liu，Ji Cai1,2; Wang，Qu Quan4

2023

10.1364/PRJ.488215

Photonics Research   Impact Factor & Quartile

2327-9125

Structured light carrying orbital angular momentum (OAM) opens up a new physical dimension for studying light–matter interactions. Despite this, the complex fields created by OAM beams still remain largely unexplored in terms of their effects on surface plasmons. This paper presents a revelation of anomalous plasmon excitations in single particles and plasmon couplings of neighboring nanorods under OAM beams, which are forbidden using non-OAM sources. The plasmon excitation of single nanoparticles is determined both by photon spin angular momentum (SAM) and OAM and influenced by the locations of the nanoparticles. Specifically, when SAM and OAM are equal in magnitude and opposite in direction, a pure plasmon excitation along light propagation direction is achieved. Two plasmon dipoles show end-to-end antibonding coupling and side-by-side bounding coupling, which are the opposite of the typical couplings. Furthermore, we observe Fano resonance with a nanorod dimer: one aligned along light propagation direction acting as the bright mode and the other aligned along the global polarization direction of light acting as the dark mode, which is the opposite of the usual plasmonic Fano resonance. By taking advantage of the unique property of the OAM source, this investigation presents a novel way to control and study surface plasmons, and the research of plasmon behavior with OAM would open new avenues for controlling electromagnetic waves and enriching the spectroscopies with more degrees of freedom.

SCI

English

Others

Ministry of Science and Technology of the People ' s Republic of China[2020YFA0211303] ; NationalNatural Science Foundation of China["11974108","12074296","12204169","12211530044"]

Optics

Optics

WOS:001051623500011

CHINESE LASER PRESS

2-s2.0-85170645926

Scopus

1.Mathematics and Physics Department,North China Electric Power University,Beijing,102206,China
2.Hebei Key Laboratory of Physics and Energy Technology,North China Electric Power University,Baoding,071000,China
3.Department of Physics,Kim Il Sung University,Pyongyang,02-381-4410,North Korea
4.Department of Physics,Southern University of Science and Technology,Shenzhen,518055,China

Yang，Da Jie,Im，Song Jin,Huang，Hai Wen,et al. Anomalous plasmon coupling and Fano resonance under structured light[J]. Photonics Research,2023,11(8):1423-1430.

Yang，Da Jie.,Im，Song Jin.,Huang，Hai Wen.,Ri，Chol Song.,Kim，Kum Dong.,...&Wang，Qu Quan.(2023).Anomalous plasmon coupling and Fano resonance under structured light.Photonics Research,11(8),1423-1430.

Yang，Da Jie,et al."Anomalous plasmon coupling and Fano resonance under structured light".Photonics Research 11.8(2023):1423-1430.