Design a Stratiform Metamaterial with Precise Optical Property

Yi-Jun Jen,Wei-Chin Liu

doi:10.3390/sym11121464

Abstract

In this work, a stratiform metamaterial is arranged as multiple periods of metal-dielectric symmetrical film stack to provide precise equivalent refractive index and admittance. There are multiple solutions of equivalent refractive index retrieved from the characteristic matrix of the film stack. The correct refractive index is derived by connecting different branches of solution at different ranges of wavelength or thickness of the dielectric layer. The refractive index of an Ag-TiO2 five-layered symmetrical film stack shown in previous work is demonstrated to be positive real instead of negative real. The associated type I iso-frequency curve supports negative refraction. In order to extend the operating wavelength of type I metamaterial, the number of the metal-dielectric symmetrical film stack is increased to reduce the thickness of the dielectric film to approach subwavelength requirement.

Highlights

A metamaterial with a negative index of refraction has been predicted to be effective for constructing a perfect lens [1]
In order to satisfy the criteria of branch selection, the correct branch solution of the refractive index was only valid for a certain range of wavelength the correct branch solution of the refractive index was only valid for a certain range of wavelength or or thickness of the dielectric layer
We clarify that the previous stratiform metamaterial is a type I

Summary

Introduction

A metamaterial with a negative index of refraction has been predicted to be effective for constructing a perfect lens [1]. Archetypical left-handed metamaterials comprise split rings as inductive-capacitive resonators, which support the simultaneous reversal of electric and magnetic responses to light at microwave frequencies [2]. The scales of resonators were shrunk to exhibit a left-handed response to light at higher frequencies, such as infrared or visible frequencies [3]. A stratiform metamaterial that comprises metal film (M) and dielectric film (D) was developed for transverse magnetic (TM) polarization mode [4]. Light incident on the side of this stack will couple to waveguide modes [5,6]. The anti-symmetry mode of the transverse electric field in a plasmonic waveguide composed of metal film (M)/dielectric film (D)/metal film (M)

Methods

Results

Conclusion