Diffusive-to-ballistic transition in dynamic light transmission through thin scattering slabs: a radiative transfer approach
Diffusive-to-ballistic transition in dynamic light transmission through thin scattering slabs: a radiative transfer approach
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DOI：
10.1364/josaa.21.001430
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发表时间：
2004-08-01
影响因子：
1.9
通讯作者：
Greffet, JJ
中科院分区：
文献类型：
--
作者：
Elaloufi, R;Carminati, R;Greffet, JJ
我们研究的偏离扩散理论，发生在动态传输的光通过薄散射板。数值求解含时辐射传输方程，得到了衰减时间和有效扩散系数D-eff。对于厚度L小于8l（tr）的系统，我们观察到了非扩散行为，其中I-tr是输运平均自由程，我们引入了一个简单的模型，给出了扩散和非扩散区域之间的过渡位置。在非扩散区域的Deff的大小依赖性强烈地受到内部反射的影响。我们表明，减少类似于50%的D-eff的实验观察[物理评论快报。79，4369（1997）]可以通过辐射传递方法再现。我们表明，辐射传输方程是一个适当的工具，研究动态光输运薄散射系统时，相干效应不起重要作用。(C)2004年美国光学学会。
We study the deviation from diffusion theory that occurs in the dynamic transport of light through thin scattering slabs. Solving numerically the time-dependent radiative transfer equation, we obtain the decay time and the effective diffusion coefficient D-eff. We observe a nondiffusive behavior for systems whose thickness L is smaller than 8l(tr), where I-tr is the transport mean free path. We introduce a simple model that yields the position of the transition between the diffusive and the nondiffusive regimes. The size dependence of Deff in the nondiffusive region is strongly affected by internal reflections. We show that the reduction of similar to50% of D-eff that was observed experimentally [Phys. Rev. Lett. 79, 4369 (1997)] can be reproduced by the radiative transfer approach. We demonstrate that the radiative transfer equation is an appropriate tool for studying dynamic light transport in thin scattering systems when coherent effects play no significant role. (C) 2004 Optical Society of America.