含金属散射体的中红外无序介质的光子定域化理论研究

基于Mie散射理论发现,各种金属在中红外区的各个频率点上的散射行为均极为相近,是一种在中红外区反照率高但散射效率较低的散射体.在浓度为10%时,介质的定域化参量最小只能达到6.6,并且与体系的常用基质材料无关.数值研究揭示了这种金属散射体系统与低吸收、高折射率散射体系统间的内在联系 关键词： 光子定域化 无序介质 中红外 Mie散射 金属

Theoretical study on mid-infrared photon localization in the media using metal spheres as random scatterers

It is pointed out that metal materials in mid-infrared region can be applied to the investigations of photon localization. Based on the Mie scattering theory at low concentration approximation in the mid-infrared region, some theoretical results are reported on the study of the localization parameter in the disordered system containing spherical metal scatterers. It is found that strong photon localization does not appear in this kind of random medium, and both of the minimum values of two localization parameters reach only about 6.6 when the volume ratio of the metals is 10%, though a single particle has a large albedo. Also, the role of the matrices in this kind of random medium on the photon localization is very different from those in the random medium containing absorption-free scatterers or abnormal dispersive dielectric scatterers, that is, has no effects on the photon localization.