Mishchenko Michael I, Liu Li, Mackowski Daniel W
Opt Lett. 2014 Mar 15;39(6):1701-4. doi: 10.1364/OL.39.001701.
We use the recently extended superposition T-matrix method to study the behavior of a sharp Lorenz-Mie resonance upon filling a spherical micrometer-sized droplet with tens and hundreds of randomly positioned microscopic inclusions. We show that as the number of inclusions increases, the extinction cross-section peak and the sharp asymmetry-parameter minimum become suppressed, widen, and move toward smaller droplet size parameters, while ratios of diagonal elements of the scattering matrix exhibit sharp angular features indicative of a distinctly nonspherical particle. Our results highlight the limitedness of the concept of an effective refractive index of an inhomogeneous spherical particle.
我们使用最近扩展的叠加T矩阵方法,来研究当一个微米级球形液滴中填充了数十个和数百个随机分布的微观内含物时,尖锐的洛伦兹-米氏共振的行为。我们表明,随着内含物数量的增加,消光截面峰值和尖锐的不对称参数最小值会受到抑制、变宽,并向更小的液滴尺寸参数移动,而散射矩阵对角元素的比值呈现出尖锐的角度特征,表明该粒子明显是非球形的。我们的结果突出了非均匀球形粒子有效折射率概念的局限性。