Nonlinear-optical susceptibilities of gases measured at 1064 and 1319 nm

The third-order nonlinear-optical susceptibilities of 16 simple atoms and molecules (Ne, Ar, Kr, Xe, H₂, D₂, N₂, O₂, CO₂, CF₄, SF₆, CH₄, C₂{H}₆$, ${C}₃H₈, n-C₄{H}₁₀$, and ${C}₄H₆) have been measured in the gas phase at two near-infrared wavelengths using the technique of electric-field-induced second-harmonic generation (ESHG) with periodic phase matching and with He as the reference gas. These results are combined with previous ESHG data in the visible region to determine dispersion curves. The experimental estimate of the static hyperpolarizability {γ} for Ne, γNe=119±{}3 a.u., is in good agreement with the best ab initio calculations, but the experimental estimates of the static hyperpolarizabilities for Ar and H₂, γAr=1167±{}20 a.u. and 〈γH2ᵉ〉=686±{}10 a.u., differ significantly from the best ab initio results.