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Ultrafast absorptive and refractive nonlinearities in multi-walled carbon nanotube film

H. I. Elim·W. Ji·G. H. Ma·K. Y. Lim·C. H. Sow·C. H. A. Huan
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Abstract

By using femtosecond laser pulses at a wavelength range from 720 to 780 nm, we have observed absorptive and refractive nonlinearities in a film of multi-walled carbon nanotubes grown mainly along the direction perpendicular to the surface of quartz substrate. The Z-scans show that both absorptive and refractive nonlinearities are of negative and cubic nature in the laser irradiance range from a few to 300 GW/cm^2. The magnitude of the third-order nonlinear susceptibility,chi-(3), is of an order of 10^-11 esu. The degenerate pump-probe measurement reveals a relaxation time of 2 ps.

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H. I. Elim, W. Ji, G. H. Ma, K. Y. Lim, C. H. Sow, C. H. A. Huan. 2003-11-11. Ultrafast absorptive and refractive nonlinearities in multi-walled carbon nanotube film. https://doi.org/10.1063/1.1786371

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