Figure 5:

Surface-like NL interaction. (a–c) Dependence of the effective NL current per unit length modulus |j _nl| over the thin film thickness d and the pump incidence angle θ and wavelength λ. (a, b) Dependence of |j _nl| over θ and d for fixed pump wavelength λ = 800 nm and (a) TE and (b) TM polarization. (c) Dependence of |j _nl| over λ and d at normal incidence. (d) Spatial dependence of the pump electric field profile modulus within the Na-based thin film rescaled to the impinging amplitude |A _in(z)|/|A ₀| at transverse electromagnetic (TEM) normal incidence for fixed wavelength λ = 800 nm and several thicknesses d = 10, 20, 50, 100, 200 nm. All plots are obtained for fixed pump intensity I ₀ = 100 GW/cm².