Winding Poynting vector of light around plasmonic nanostructure
Journal
Journal of Quantitative Spectroscopy and Radiative Transfer
Journal Volume
278
Date Issued
2022
Author(s)
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. ? 2021
Subjects
Boundary element method
Fredholm integral equation of the second kind
Green's function
Kernel function
Method of moments
N × RWG
Nanocuboid
Optical vortex
Poynting vector
Spin-orbit interaction
Stratton-Chu formulation
Surface charge
Surface current
Surface integral equations
Surface plasmon resonance
Gold
Integral equations
Nanostructures
Plasmonics
Sailing vessels
Titanium dioxide
Vectors
Vortex flow
Winding
Boundary-element methods
Fredholm's integral equation
Greens function
Optical vortices
Poynting's vectors
Stratton-chu formulation
Surface-plasmon resonance
Electromagnetic waves
Type
journal article