Fig. 1. (a) Nonlinear optical experimental setup. (b) Microscopic image of the fabricated sample surface of a typical CPPLN structure. (c) High-magnification view of the CPPLN sample. (d) Fabricated CPPLN sample. (e) The phase-mismatch curve for the SHG process in LN crystal combined with the Fourier-transform spectrum for CPPLN structure. (f) Photographs of the water–CPPLN module illuminated by the 800 nm Ti:sapphire laser. (g) The white-light spot emitting from the water–CPPLN module.

Fig. 2. Normalized supercontinuum spectra taken after water with different input pulse energies.

Fig. 3. Normalized supercontinuum spectra emitting from the water–CPPLN module at different input pulse energies and incident light spot diameters.

Fig. 4. (a) Simulated output spectra via SPM from water at different input energies. (b) Simulated spectral evolution at different positions within a 40 mm-length water at 4 mJ pump pulse energy. (c) Linear fitting processes modeling the supercontinuum experiment within water under the pump of 4 mJ pulse energy.