Winding Poynting vector of light around plasmonic nanostructure. (February 2022)

• Record Type: Journal Article
• Authors: Ku, Yun-Cheng; Kuo, Mao-Kuen; Liaw, Jiunn-Woei
• Is Part Of: Journal of quantitative spectroscopy & radiative transfer. Volume 278(2022)
• Publication Date: 2022-02
• Subjects: Stratton-Chu formulation -- Surface integral equations -- Boundary element method -- Kernel function -- Green's function -- Method of moments -- N × RWG -- Fredholm integral equation of the second kind -- Surface plasmon resonance -- Surface charge -- Surface current -- Poynting vector -- Nanocuboid -- Optical vortex -- Spin-orbit interaction; BEM Boundary element method -- CP Circularly polarized -- EM Electromagnetic -- FDTD Finite difference time domain -- FEM Finite element method -- MoM Method of moment -- NP Nanoparticle -- OAM Orbital angular momentum -- PICS Plasmon-induced charge separation -- RCP Right-handed circularly polarized -- RWG Rao-Wilton-Glisson -- SAM Spin angular momentum -- SIEs Surface integral equations -- SIRs Surface integral representations -- SOI Spin-orbit interaction -- SPR Surface plasmon resonance; Spectrum analysis -- Periodicals; Radiation -- Periodicals; Analyse spectrale -- Périodiques; Rayonnement -- Périodiques; Radiation; Spectrum analysis; Periodicals; 543.0858
• DOI: 10.1016/j.jqsrt.2021.108005
• Languages: English
• ISSNs: 0022-4073

Abstract

Highlight: Surface integral equations of Fredholm equations is used to study 3D light-matter interaction. Streamline of Poynting vector winds along the long axis of a gold nanocuboid as irradiated by a circularly polarized light. Two vortexes of energy flux winding around specific corners of a gold nanocuboid are generated in the presence of a TiO2 substrate. Our simulation method provides a deeper insight into the nanoscale light-matter interaction. Abstract: A set of surface integral equations (SIEs) of Fredholm equations of the second kinds is used to study 3D light-matter interaction at the nanoscale, particularly for the plasmonic effect. Based on this method, we find that the streamline of Poynting vector (energy flux) winds along the long axis of a gold nanocuboid as irradiated by a circularly polarized light propagating in the short-axis direction; the transverse angular momentum is caused by the spin-orbit interaction of light via a plasmonic nanostructure. The spiral winding behavior of Poynting vector could be related to the helical surface currents. Moreover, we find that at an off-resonance frequency two vortexes of energy flux winding around specific corners of a gold nanocuboid are generated in the presence of a TiO2 substrate. This phenomenon may explain the cause of the selectivity of active sites for plasmon-enhanced chemical reaction. Our simulation method provides a deeper insight into the nanoscale light-matter interaction.