负折射率与负指数材料的物理原理

负折射率

双负材料

需积分: 10 70 浏览量更新于2024-07-17 收藏 8.59MB PDF 举报

身份认证购VIP最低享 7 折!

领优惠券(最高得80元）

资源详情

资源推荐

XVI List of Contributors

Yuri S. Kivshar

Nonlinear Physics Centre and Center

for Ultra-High Bandwidth Devices

for Optical Systems (CUDOS)

Research School of Physical Sciences

and Engineering

Australian National University

Canberra, ACT 0200, Australia

ysk@internode.on.net

Cliﬀord M. Krowne

Microwave Technology Branch

Electronics Science and Technology

Division

Naval Research Laboratory

Washington, DC 20375-5347

krowne@webbsight.nrl.navy.mil

Jensen Li

Physics Department

Hong Kong University of Science

and Technology

Clear Water Bay, Hong Kong, China

Zhi-Yuan Li

Institute of Physics

Chinese Academy of Sciences

Beijing 100080

Zifang Lin

Bartol Research Institute

and Department of Physics

and Astronomy

University of Delaware

Newark, DE 19711, USA

Z.Y. Liu

Physics Department

Wuhan University

Wuhan, China

Peter F. Loschialpo

Naval Research Laboratory

Washington, DC 20375

Wentao Lu

Department of Physics

and Electronic Materials

Research Institute

Northeastern University

Boston, MA 02115, USA

w.lu@neu.edu

Angelo Mascarenhas

Materials Science Center

National Renewable Energy

Laboratory (NREL)

1617 Cole Blvd.

Golden, CO 80401, USA

Ekmel Ozbay

Nanotechnology Research Center

Department of Physics

and Department of Electrical

and Electronics Engineering

Bilkent University

Bilkent, 06800 Ankara, Turkey

ozbay@bilkent.edu.tr

Gonca Ozkan

Nanotechnology Research Center

Bilkent University

Bilkent 06800, Ankara, Turkey

Claudio G. Parazzoli

Boeing Phantom Works

Seattle, WA 98124

Frederic Rachford

Material Science and Technology

Division

Naval Research Laboratory

Washington, DC 20375

rachford@anvil.nrl.navy.mil

Ilya V. Shadrivov

Nonlinear Physics Centre

Research School of Physical Sciences

and Engineering

Australian National University

Canberra ACT 0200, Australia

Negative Refraction of Electromagnetic

and Electronic Waves in Uniform Media

Y. Zhang and A. Mascarenhas

Summary. We discuss various schemes that have been used to realize negative

refraction and zero reﬂection, and the underlying physics that dictates each scheme.

The requirements for achieving both negative refraction and zero reﬂection are

explicitly given for diﬀerent arrangements of the material interface and diﬀerent

structures of the electric permittivity tensor ε. We point out that having a left-

handed medium is neither necessary nor suﬃcient for achieving negative refraction.

The fundamental limitations are discussed for using these schemes to construct a

perfect lens or “superlens,” which is the primary context of the current interest in

this ﬁeld. The ability of an ideal “superlens” beyond diﬀraction-limit “focusing” is

contrasted with that of a conventional lens or an immersion lens.

1.1 Introduction

1.1.1 Negative Refraction

Recently, negative refraction has attracted a great deal of attention, largely

due to the realization that this phenomenon could lead to the development

of a perfect lens (or superlens) [1]. A perfect lens is supposed to be able to

focus all Fourier components (i.e., the propagating and evanescent modes)

of a two-dimensional (2D) image without missing any details or losing any

energy. Although such a lens has yet to be shown possible either physically

and practically, the interest has generated considerable research in electromag-

netism and various interdisciplinary areas in terms of fundamental physics and

material sciences [2–4]. Negative refraction, as a physical phenomenon, may

have much broader implications than making a perfect lens. Negative refrac-

tion achieved using diﬀerent approaches may involve very diﬀerent physics

and may ﬁnd unique applications in diﬀerent technology areas. This chapter

intends to oﬀer some general discussion that distinguishes the underlying

physics of various approaches, bridges the physics of diﬀerent disciplines

(e.g., electromagnetism and electronic properties of the material), and pro-

vides some detailed discussions for one particular approach, that is, negative

2 Y. Zhang and A. Mascarenhas

refraction involving uniform media with conventional dielectric properties. By

uniform medium we mean that other than the microscopic variation on the

atomic or molecular scale the material is spatially homogeneous.

The concept of negative refraction was discussed as far back as 1904 by

Schuster in his book An Introduction to the Theory of Optics [5]. He indicated

that negative dispersion of the refractive index, n, with respect to the wave-

length of light, λ, i.e., dn/dλ<0, could lead to negative refraction when light

enters such a material (from vacuum), and the group velocity, v

,isinthe

opposite direction to the wave (or phase) velocity, v

. Although materials with

dn/dλ<0 were known to exist even then (e.g., sodium vapor), Schuster stated

that “in all optical media where the direction of the dispersion is reversed,

there is a very powerful absorption, so that only thicknesses of the absorb-

ing medium can be used which are smaller than a wavelength of light. Under

these circumstances it is doubtful how far the above results have any applica-

tion.” With the advances in material sciences, researchers are now much more

optimistic 100 years later. Much of the intense eﬀort in demonstrating a “poor

man’s” superlens is directed toward trying to overcome Schuster’s pessimistic

view by using the spectral region normally having strong absorption and/or

thin-ﬁlm materials with ﬁlm thicknesses in the order of (or even a fraction of)

the wavelength of light [2]. However, with regard to the physics of refraction,

for a “lens” of such thickness, one may not be well justiﬁed in viewing the

transmission as refraction, because of various complications (e.g., the ambi-

guity in deﬁning the layer parameters [6] and the optical tunnel eﬀect [7]).

The group velocity of a wave, v

(ω, k)=dω/dk, is often used to describe

the direction and the speed of its energy propagation. For an electromagnetic

wave, strictly speaking, the energy propagation is determined by the Poynting

vector S. In certain extreme situations, the directions of v

and S could even

be reversed [8]. However, for a quasimonochromatic wave packet in a medium

without external sources and with minimal distortion and absorption, the

direction of S does coincide with that of v

[9]. For simplicity, we will focus

on the simpler case, where the angle between v

and wave vector k is of

signiﬁcance in distinguishing two types of media: when the angle is acute or

k · v

> 0, it is said to be a right-handed medium (RHM); when the angle is

obtuse or k ·v

< 0, it is said to be a left-handed medium (LHM) [10]. If one

prefers to deﬁne the direction of the energy ﬂow to be positive, an LHM can

be referred to as a material with a negative wave velocity, as Schuster did in

his book. A wave with k ·v

< 0 is also referred to as a backward wave (with

negative group velocity), in that the direction of the energy ﬂow is opposite

to that of the wave determined by k [11, 12]. Lamb was perhaps the ﬁrst to

suggest a one-dimensional mechanical device that could support a wave with

a negative wave velocity [13], as mentioned in Schuster book [5]. Examples of

experimental demonstrations of backward waves can be found in other review

papers [4, 14]. Unusual physical phenomena are expected to emerge either in

an individual LHM (e.g., a reversal of the group velocity and a reversal of

Doppler shift) or jointly with an RHM (e.g., negative refraction that occurs

1 Negative Refraction of Electromagnetic and Electronic Waves 3

at the interface of an LHM and RHM) [10]. The eﬀect that has received most

attention lately is the negative refraction at the interface of an RHM and

LHM, which relies on the property k · v

< 0intheLHM.

There are a number of ways to realize negative refraction [4]. Most ways

rely on the above-mentioned LH behavior, i.e., k · v

< 0, although LH

behavior is by no means necessary or even suﬃcient to have negative

refraction. Actually, LH behavior can be readily found for various types

of wave phenomena in crystals. Examples may include the negative disper-

sion of frequency ω(k) for phonons and of energy E(k) for electrons; however,

they are inappropriate to be considered as uniform media and thus to discuss

refraction in the genuine sense, because the wave propagation in such media is

diﬀractive in nature. For a simple electromagnetic wave, it is not trivial to ﬁnd

a crystal that exhibits LH behavior. By “simple electromagnetic wave,” we

refer to the electromagnetic wave in the transparent spectral region away from

the resonant frequency of any elementary excitation in the crystal. In this

case, the light–matter interaction is mainly manifested as a simple dielectric

function ε(ω), as in the situation often discussed in crystal optics [15], where

ε(ω) is independent of k.

1.1.2 Negative Refraction with Spatial Dispersion

The ﬁrst scheme to be discussed for achieving negative refraction relies on

the k dependence of ε to produce the LH behavior. The dependence of ε(k)

or n(λ) is generally referred to as spatial dispersion [16, 17], meaning that

the dielectric parameter varies spatially. Thus, this scheme may be called

the spatial-dispersion scheme. The negative refraction originally discussed by

Schuster in 1904 could be considered belonging to this scheme, although the

concept of spatial dispersion was only introduced later [17] and discussed in

greater detail in a book by Agranovich and Ginzburg, Spatial Dispersion in

Crystal Optics and the Theory of Excitons [9]. If one deﬁnes v

= ω/k = c/n,

and assumes n>0, then according to Schuster, v

is related to v

by [5]

= v

− λ

dλ

, (1.1)

and the condition for having a negative wave velocity is given as λ dv

/dλ>

, which is equivalent to dn/dλ<−n/λ < 0. Negative group velocity and

negative refraction were speciﬁcally associated with spatial dispersion by

Ginzburg and Agranovich [9, 17]. Recently, a generalized version of this con-

dition has been given by Agranovich et al. [18]. In their three-ﬁelds (E, D, B)

approach, with a generalized permittivity tensor ˜ε(ω, k) (see the chapter

of Agranovich and Gartstein for more details), the time-averaged Poynting

vector in an isotropic medium is given as

S =

8π

Re(E

∗

xB) −

16π

∇

˜ε(ω,k)E

∗

E, (1.2)

剩余389页未读，继续阅读

sinat_39214299

粉丝: 1
资源: 18

负折射率与负指数材料的物理原理

Unity 3D-Suimono Water System

unity雨水插件

SUIMONO Water System 2.1.6 逼真的水系统.zip

jet refraction 射流折射

电离层衰减公式参考文献

Templar Assassin

帮我写一份用Python代码模拟光的折射的代码

unity 科技球shader

帮我写一个ue高级水材质

用matlab模拟光经过两层折射率不同的介质时p位置的点扩散函数强度轴向分布

将自然光转换成线偏振光的金属超表面，给出相关文献

光线跟踪递归函数伪代码

unity2019 实时折射shader

Shader Graph怎么用节点连接一个玻璃材质

unity URP 玻璃shader

国内外关于折射波偏移成像的文献都有哪些，分别介绍了什么？

无线电波的传播方式有哪些

unity2019 内置管线实时折射反射shader

光线追踪方法的伪代码

最新资源