Pulse duration and wavelength effects on optical limiting behaviour in carbon nanotube suspensions

Carbon nanotubes exhibit good optical limiting performances for a range of wavelengths from 400 nm to 1100 nm. There is a strong nonlinear scattering due to heat transfer from particles to solvent leading to vapor growth around the particles. There is also a phase change of carbon nanotubes including optical limiting behaviour for pulse duration of about 5 ns. The optical limiting performances can be studied as a function of the pulse duration by carrying out nonlinear transmittance with f/30 focussing geometry for different pulse durations and wavelengths.