Generation of Bessel Surface Plasmon Polaritons in a Finite-Thickness Metal Film

S N Kurilkina,N S Kazak,V N Belyi

doi:10.1155/2013/253692

Abstract

A theory of generation of low- and high-index Bessel surface plasmon polaritons and their superposition in a metal film of a finite thickness is developed. Correct analytical expressions are obtained for the field of two families of Bessel surface plasmon polariton modes formed inside and outside the metal layer. The intensity distribution near the boundary of the layer has been calculated and analyzed. A scheme for the experimental realization of a superposition of Bessel surface plasmon polaritons is suggested. Our study demonstrates that it is feasible to use the superposition of Bessel surface plasmon polaritons as a virtual tip for near-field optical microscopy with a nanoscale resolution.

Highlights

Surface plasmon polaritons (SPPs) are surface electromagnetic waves related to collective electron oscillations near the metal surface excited by light [1,2,3]
The complex Bessel surface plasmon polariton mode effective indices we found are n1∗ = 1.874 + 0.012i and n2∗ = 2.179 + 0.073i
The comparison was made of Bessel surface plasmon polaritons investigated in this paper and traditional surface plasmon polaritons

Summary

Introduction

Surface plasmon polaritons (SPPs) are surface electromagnetic waves related to collective electron oscillations near the metal surface excited by light [1,2,3]. Despite of intensive theoretical and experimental investigations up to now there is no detailed analysis of the problem of generation of different types of Bessel surface plasmon polaritons in the structure including a metallic absorbing layer separating a substrate and targeted (dielectric) medium. (7a), (7b), (8a), (8b), and (12) at q, which meets condition (11), describe Bessel surface plasmon polaritons formed in the structure “dielectric substrate metal layer dielectric.”. The SPP propagating in the metal film is excited by every p-polarized plane-wave component of the incident BLB in conditions of the plasmon resonance. There occurs the generation of pairs of two counter-propagating SPP waves with the wave vectors ±q.⃗ The generated SPPs will propagate in all the possible radial directions to form a localized SPP field This results in a complex high-symmetric interference light structure emerging in sections parallel to the metal-dielectric surface. The limited narrow Bessel light beam of radius r0 in the

The phase of F Derivative of the phase of F

Conclusion