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arXiv · 1010.5231

Tunable asymmetric reflectance in silver films near the percolation threshold

Aiqing Chen·Miriam Deutsch
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Abstract

We report on the optical characterization of semicontinuous nanostructured silver films exhibiting tunable optical reflectance asymmetries. The films are obtained using a multi-step process, where a nanocrystalline silver film is first chemically deposited on a glass substrate and then subsequently coated with additional silver via thermal vacuum-deposition. The resulting films exhibit reflectance asymmetries whose dispersions may be tuned both in sign and in magnitude, as well as a universal, tunable spectral crossover point. We obtain a correlation between the optical response and charge transport in these films, with the spectral crossover point indicating the onset of charge percolation. Such broadband, dispersion-tunable asymmetric reflectors may find uses in future light-harvesting systems.

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Aiqing Chen, Miriam Deutsch. 2011-04-12. Tunable asymmetric reflectance in silver films near the percolation threshold. https://doi.org/10.1063/1.3585873

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