Direct Measurements of the Nonlinear Index of Refraction of Water at 815 and 407 nm Using Single-Shot Supercontinuum Spectral Interferometry

Single-shot supercontinuum spectral interferometry was used to measure the nonlinear index of refraction due to the optical Kerr effect in water at both 815 and 407 nm, with pump pulse lengths of ∼ 90 and ∼ 250 fs, respectively. Knowledge of the nonlinear index at 407 nm allows pulse tailoring to achieve remote underwater pulse compression and self-focusing.