概括
这项研究澄清了吸收材料中的颗粒的灭绝定义. 它揭示了宿主吸收显著影响无效灭绝,使消极灭绝截面和更好地了解辐射转移.
科学领域:
- 光学和光子学 在光学和光子学.
- 材料科学 材料科学 材料科学
- 电磁主义 电磁主义
背景情况:
- 关于吸收宿主中的颗粒的灭绝和衰减存在争议,这阻碍了对复合材料辐射转移的理解.
- 现有的灭绝定义 (等价定理,近场分析,操作) 有局限性,特别是在宿主吸收和远场效应方面.
研究的目的:
- 概述和比较吸收介质中颗粒的现有灭绝定义.
- 为了研究宿主吸收对空洞灭绝的影响,使用一个通用的操作定义.
- 为了更清楚地了解空洞复合材料中的辐射转移.
主要方法:
- 审查和分析现有的灭绝定义,包括等效定理,近场分析定义和操作定义.
- 独立散射近似和严格的多重散射理论的应用.
- 使用马克斯韦-加内特有效介质理论计算含空气材料 (SiC,Ag) 的衰减系数.
主要成果:
- 灭绝的概括操作定义在特定的近似下被证明与有效的媒介方法相当.
- 主体吸收显著影响空洞灭绝,导致空洞共振的正,零甚至负灭绝截面.
- 相当性定理和近场定义未能捕捉空气共振结构和吸收介质中的负灭绝.
结论:
- 一般化的操作灭绝定义准确地解释了宿主吸收效应,解决了以前的限制.
- 消极的灭绝截面,表明总吸收减少,是可能的,并通过宿主吸收进行定量控制.
- 这些发现增强了对复杂的散射现象和吸收复合材料中的辐射转移的理解.
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