Nonlinear refraction and absorption of spectrally tuneable picosecond pulses in carbon disulfide

Abstract We analyze the spectral dependence of the nonlinear refractive index and nonlinear absorption coefficient of carbon disulfide (CS2) in the spectral range of 400–1100 nm using picosecond laser pulses. An increase of the nonlinear refractive index of CS2 at the shorter wavelength region compared with the near infrared region (9 × 10−14 cm2 W−1 (λ = 700 nm) and 4 × 10−14 cm2 W−1 (λ = 1000 nm), respectively) follows by a decrease of this parameter at the wavelengths below 600 nm. We compare the spectral dependences of the lower- and higher-order nonlinear absorption coefficients in carbon disulfide. The three-photon absorption coefficient was found to be maximal at λ = 1000 nm (β3PA = 2 × 10−19 cm3 W−2), while analyzing between 700 and 1100 nm. The maximal value of the two-photon absorption coefficient was determined at λ = 400 nm (1.8 × 10−9 cm W−1).