Spectral resolved study of filamentation effect on the nonlinear absorption in carbon disulfide

A Z-scan system using spectrometers as detectors is established to investigate nonlinear absorption and white light continuum separately, in which absorption coefficient that is coincident with previous work was obtained. After Z-scan experiments, spot photographs were captured to further study the spatial properties of filaments in CS₂, and we obtained similar space between dual filaments with previous work. Using the experimental setup, we find that plasma generation is the main effect impacting the nonlinear absorption and refraction process, and this impact can be eliminated in the case of CS₂. Therefore, effect of filamentation can be neglected for CS₂. Though it is easy to generate filaments in CS₂ at relatively low intensity, fitting the Z-scan curve with three-photon model at 800 nm for CS₂ is reasonable. In addition, the thickness of sample can affect extracted absorption coefficient of CS₂ by affecting the length of filamentation.