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arXiv · 1001.1066

Optimal Concentration of Light in Turbid Materials

E. G. van Putten·A. Lagendijk·A. P. Mosk
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Abstract

In turbid materials it is impossible to concentrate light into a focus with conventional optics. Recently it has been shown that the intensity on a dyed probe inside a turbid material can be enhanced by spatially shaping the wave front of light before it enters a turbid medium. Here we show that this enhancement is due to concentration of light energy to a spot much smaller than a wavelength. We focus light on a dyed probe sphere that is hidden under an opaque layer. The light is optimally concentrated to a focus which does not exceed the smallest focal area physically possible by more than 68%. A comparison between the intensity enhancements of both the emission and excitation light supports the conclusion of optimal light concentration.

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E. G. van Putten, A. Lagendijk, A. P. Mosk. 2010-01-07. Optimal Concentration of Light in Turbid Materials. https://doi.org/10.1364/josab.28.001200

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