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arXiv · 1611.00238

Optothermal nonlinearity of silica aerogel

Maria Chiara Braidotti·Silvia Gentilini·Adam Fleming·Michiel C. Samuels·Andrea Di Falco·Claudio Conti
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Abstract

We report on the characterization of silica aerogel thermal optical nonlinearity, obtained by z-scan technique. The results show that typical silica aerogels have nonlinear optical coefficient similar to that of glass $(\simeq 10^{-12} $m$^2/$W), with negligible optical nonlinear absorption. The non\-li\-near coefficient can be increased to values in the range of $10^{-10} $m$^2/$W by embedding an absorbing dye in the aerogel. This value is one order of magnitude higher than that observed in the pure dye and in typical highly nonlinear materials like liquid crystals.

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Maria Chiara Braidotti, Silvia Gentilini, Adam Fleming, Michiel C. Samuels, Andrea Di Falco, Claudio Conti. 2016-11-01. Optothermal nonlinearity of silica aerogel. https://doi.org/10.1063/1.4959240

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