Simulation of light focusing by a dielectric microcylinder with a metal film and gap on shadow side

Abstract

In this work, using the FullWAVE software package, numerical simulation of focusing of TM-wave with a wavelength of 633 nm was performed. It is shown that a dielectric microcylinder made of polyester with a radius of 2.1749 of wavelength coated on the shadow side with a silver film of 90 nm with a 100 nm hole, allows to get a focus with a maximum intensity of 1.37 times more (10.61 a. u), than a conventional dielectric cylinder (7.73 a. u).

Numerical Modeling of Radiation Focusing by Dielectric Microcylinders with Several Layers

“…The improvements are often made to the design of the focusing optical element for optimization of the nanojet parameters. For example, metal cores [27,28] and shells [29,30], multilayer dielectric structures [31,32] can be used. Two types of spheres: an ordinary dielectric…”

“…In Ref. [30], we proposed an unusual design of a polyester cylinder with silver film and a gap on the shadow side. A series of numerical simulations were carried out in which the hole diameter was varied.…”