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arXiv · 0710.2721

Large nonlinear absorption and refraction coefficients of carbon nanotubes estimated from femtosecond Z-scan measurements

N. Kamaraju·Sunil Kumar·Srinivasan Krishnamurthy·Shekhar Guha·A. K. Sood·C. N. R. Rao
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Abstract

Nonlinear transmission of 80 and 140 femtosecond pulsed light with $0.79 μm$ wavelength through single walled carbon nanotubes suspended in water containing sodium dodecyl sulphate is studied. Pulse-width independent saturation absorption and negative cubic nonlinearity are observed, respectively, in open and closed aperture Z-scan experiments. The theoretical expressions derived to analyze the z-dependent transmission in the saturable limit require two photon absorption coefficient $β_0\sim$ $1.4 cm/MW$ and a nonlinear index $γ\sim -5.5 \times10^{-11} cm^2/W$ to fit the data.

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N. Kamaraju, Sunil Kumar, Srinivasan Krishnamurthy, Shekhar Guha, A. K. Sood, C. N. R. Rao. 2007-12-09. Large nonlinear absorption and refraction coefficients of carbon nanotubes estimated from femtosecond Z-scan measurements. https://doi.org/10.1063/1.2825409

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