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arXiv · 1106.2732

Testing the diffusion hypothesis as a mechanism of self-healing in Disperse orange 11 doped in PMMA

Abstract

In this work, we show that reversible photodegradation of Disperse Orange 11 doped in PMMA is not due to dye diffusion - a common phenomenon observed in many dye-doped polymers. The change in linear absorbance due to photodegradation of the material shows an isobestic point, which is consistent with the formation of a quasi-stable damaged species. Spatially-resolved amplified spontaneous emission and fluorescence, both related to the population density, are measured by scanning the pump beam over a burn mark. A numerical model of the time evolution of the population density due to diffusion is inconsistent with the experimental data suggesting that diffusion is not responsible.

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Shiva K. Ramini, Nathan Dawson, Mark G. Kuzyk. 2011-06-10. Testing the diffusion hypothesis as a mechanism of self-healing in Disperse orange 11 doped in PMMA. https://doi.org/10.1364/josab.28.002408

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