摘要外界入射辐射在与介质相互作用的过程中,会将其所携带的能量和动量传递给介质,含颗粒球复合材料也不例外,但是由于其微结构的改变,在特定情况下其宏观等效介电常数和等效磁化系数的实部会同时为负,如果采用常规能量密度的定义式,会导致所求的辐射吸收能量为负值的情况,这是不符合物理规律的。针对这一事实,首先介绍了负折射材料的理论起源和几种重要的电磁特性,并对负折射材料的应用前景进行了展望。然后基于电磁理论和能量守恒原理,利用电偶极子和磁偶极子模型推导出负折射材料中的能量密度, 最后利用推导出的能量密度公式计算了含颗粒球负折射材料的辐射能量密度。 关键词 负折射材料 等效介电常数 等效磁导率 电磁能量密度 复折射率10216
Title Analysis of radiance energy for negative refractive
index material containing ball particles
Abstract
In the process of interaction between the incident radiation from outside
and the medium, the energy and momentum carried by the incident radiation
will transfer to the medium, as well as composite materials that contain
particle ball. But because of the change of its micro-structure, in special
case, the real part of its macro equivalent permittivity and equivalent
susceptibility will be negative at the same time. If using conventional
energy density definition type, the absorption of radiation energy that
we need will be negative, which is not in accord with the physical law.
In view of this fact, the paper first introduces the theory of negative
refractive index material and several important electromagnetic
characteristics, and then presents the prospect of the application of the
negative refractive index material. The energy density associated with an
electromagnetic wave passing through a medium, in which both the
permittivity and the permeability are dispersive and absorptive, is
derived. Finally, by the using of the energy density formula deduced, we
calculated the energy density of radiation for negative refractive index
material containing ball particles.
Keywords Left-handed materials, negative permittivity, negative-
Permeability, Electromagnetic energy density
目 录
第1章 引言 2
1.1 负折射材料的理论根源.. 2
1.2 负折射材料的研究意义及现状.. 5
1.3 本文的主要内容 . 7
第2章 左手材料基本理论及电磁特性.. 7
2.1左手材料基本理论.. 7
2.2 左手材料的几种重要电磁特性 . 9
2.2.1逆多普勒(Doppler)效应 . 9
2.2.2 负折射现象.. 10
2.2.3 逆切伦科夫(Cerenkov)辐射效应 12
2.2.4 完美透镜. 13
2.3 左手材料的应用与展望 15
第3章 负折射材料中的电磁能量密度分析 16
3.1 引言 16
3.2 理论推导 17
3.3 数值计算. 19
结 论.. 23
致 谢.. 24
参考文献.. 25
附 录.. 27
第 1 章 引言
“负折射”材料顾名思义就是折射率为负的一类材料,这种材料又被称作左
手材料(LHM),左手材料(LHM)这一概念最早是由前苏联科学家 Veselago[1]
在
1968 年提出的,他从麦克斯韦方程出发,分析了电磁波在介电常数和磁导率同
时为负介质中传播的状况,从理论上指出这种介质的存在是不违反物理学定律的,
并且具有负折射效应、逆多普勒效应、逆切伦科夫辐射、完美透镜等奇异物理现