The influence of nonlinear scattering light distributions on the optical limiting properties of carbon nanotubes

The optical limiting (OL) properties of carbon nanotubes (CNTs) with different lengths were investigated using a nanosecond pulse laser. Experimental results showed that the OL behaviour of CNTs dispersion with shorter tube length and smaller bundle size was much better than for those with a longer length and larger bundle size. The nonlinear scattering experiments and numerical modelling results indicated that forward scattering light played an important role in deteriorating the OL property of longer CNTs. By removing parts of the forward scattering light using an aperture placed before the detector, the OL properties of materials could be improved.