English
Related papers

Related papers: Why is the refractive index cannot be negative

200 papers

It is generally believed that Veselago's criterion for negative refraction cannot be fulfilled in natural materials. However, considering imaginary parts of the permittivity ({\epsilon}) and permeability ({\mu}) and for metals at not too…

Materials Science · Physics 2015-05-20 Sebastian Engelbrecht , Alexey Mikhailovich Shuvaev , Y. Luo , V. Moshnyaga , Andrei Pimenov

This paper is devoted to investigating the physically interesting optical and electromagnetic properties, phenomena and effects of wave propagation in the negative refractive index materials, which is often referred to as the {\it…

Materials Science · Physics 2007-05-23 Jian Qi Shen

The planewave response of a linear passive material generally cannot be characterized by a single scalar refractive index, as directionality of energy flow and multiple wavevectors may need to be considered. This is especially significant…

Optics · Physics 2009-06-15 Tom G. Mackay , Akhlesh Lakhtakia

Perfect lensing and cloaking based on complementary media are possible applications of negative refractive index materials. Metamaterials represent the natural candidates to realize such property by tailoring the effective dielectric…

Materials Science · Physics 2010-01-31 Claudio Amabile , Enrico Prati

There exists a class of realizable, active media for which the refractive index cannot be defined as an analytic function in the upper half-plane of complex frequency. The conventional definition of the refractive index based on analyticity…

Optics · Physics 2009-11-11 Johannes Skaar

We show that an electromagnetic (EM) wave undergoes negative refraction at the interface between a positive and negative refractive index material. Finite difference time domain (FDTD) simulations are used to study the time evolution of an…

Condensed Matter · Physics 2009-11-07 S. Foteinopoulou , E. N. Economou , C. M. Soukoulis

The Bragg regime shifts when conventional materials in a multilayer distributed Bragg reflector (DBR) are replaced by artificial materials with the so-called negative index of refraction. This provides an avenue for characterizing the…

Classical Physics · Physics 2007-05-23 Jaline Gerardin , Akhlesh Lakhtakia

We demonstrate negative refraction of microwaves in metallic photonic crystals. The spectral response of the photonic crystal, which manifests both positive and negative refraction, is in complete agreement with band-structure calculations…

Materials Science · Physics 2009-11-10 P. V. Parimi , W. T. Lu , P. Vodo , J. Sokoloff , S. Sridhar

An effective medium model is developed for disordered metamaterials containing a spatially random distribution of dielectric spheres. Similar to effective medium models for ordered metamaterials, this model predicts resonances in the…

Optics · Physics 2017-03-09 Brian A Slovick

The feasibility and extraordinary properties of mirrorless parametric oscillations in strongly absorbing negative-index metamaterials are shown. They stem from the backwardness of electromagnetic waves inherent to this type of…

The refractive index of a dielectric medium comprising both passive and inverted components in its permittivity was determined using two methods: (i) in the time domain, a finite-difference algorithm to compute the frequency-domain…

Optics · Physics 2007-12-07 Joseph B. Geddes , Tom G. Mackay , Akhlesh Lakhtakia

In this paper we show that a negative index of refraction is not a direct implication of transformation optics with orientation-reversing diffeomorphisms. Rather a negative index appears due to a specific choice of sign freedom.…

Optics · Physics 2011-02-02 Luzi Bergamin , Alberto Favaro

In recent years a very exciting and intense activity has been devoted to the understanding and construction of materials that enjoy exotic optical properties, such as a negative refractive index. Motivated by these experimental and…

High Energy Physics - Theory · Physics 2011-04-20 A. Amariti , D. Forcella , A. Mariotti , G. Policastro

We analyze wave scattering by an interface between a positive refractive index medium and a Left-Handed Material. We show that the negative refraction effect can be deduced directly from Maxwell equations, without references to causality or…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Didier Felbacq

We reconsider the refraction of evanescent waves at an interface between air and negative index medium under the assumption that negative index medium is necessarily dispersive and lossy. We show that all evanescent waves in air will be…

Optics · Physics 2009-06-26 Weiguo Yang , John O. Schenk , Michael A. Fiddy

A type of 3-dimensional optical negative-refractive-index metamaterials composed of all dielectric nanospheres is proposed and demonstrated theoretically. The metamaterials are constructeded by pairing together two kinds of dielectric…

We systematically examine the conditions of obtaining left-handed (LH) behavior in photonic crystals. Detailed studies of the phase and group velocities as well as the phase np and group ng refractive index are given. The existence of…

Condensed Matter · Physics 2009-11-07 S. Foteinopoulou , C. M. Soukoulis

The aim of this paper is to provide a mathematical theory for understanding the mechanism behind the double-negative refractive index phenomenon in chiral materials. The design of double-negative metamaterials generally requires the use of…

Analysis of PDEs · Mathematics 2017-12-11 Habib Ammari , Wei Wu , Sanghyeon Yu

We report experiments of light transmissivity at wavelengths: 532 and 400 nm, through an Au film with a wedge shape. Our results mimic the negative refraction reported by others for so-called left handed materials. A mimic of negative…

Condensed Matter · Physics 2012-08-27 M. Sanz , A. C. Papageorgopoulos , W. F. Egelhoff , M. Nieto-Vesperinas , N. Garcia , .

Refraction of obliquely incident plane waves due to the interface of a vacuous half-space and a half-space occupied by a simply moving, nondissipative, isotropic dielectric-magnetic medium is considered, when the medium's velocity lies…

Optics · Physics 2007-05-23 Tom G. Mackay , Akhlesh Lakhtakia