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Ultrafast Optical Nonlinearity in PMMA-TiO2 Nanocomposites

H. I. Elim·W. Ji·A. H. Yuwono·J. M. Xue·J. Wang
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Abstract

With 780-nm, 250-fs laser pulses, ultrafast optical nonlinearity has been observed in a series of thin films containing PMMA-TiO2 nanocomposites, which are synthesized by a simple technique of in-situ sol-gel/polymerization. The best figures of merit are found in one of the films prepared with a 60% weight percentage of titanium isopropoxide. TEM shows the presence of the 5-nm-diameter particles in the film. The observed optical nonlinearity has a recovery time of ~1.5 ps. These findings suggest the strong potential of PMMA-TiO2 nanocomposites for all-optical switching.

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H. I. Elim, W. Ji, A. H. Yuwono, J. M. Xue, J. Wang. 2003-02-27. Ultrafast Optical Nonlinearity in PMMA-TiO2 Nanocomposites. https://doi.org/10.1063/1.1568544

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