Fig. 4: Representative Performance of the Cascaded OPG-DFG processes.
From: Cascaded nonlinear down-conversion in poling-free lithium niobate nanophotonic waveguides
a The intensities of OPG and cascaded process versus the input pump energy for the reverse-polarization dual-layer nanophotonic TFLN waveguide. b The measured cascaded efficiency and output power as a function of the pump energy. c Tunable central wavelength generated by the cascaded process and tunable pump wavelength versus the pump energy. Left: cascaded OPG-DFG process. Right: spectral broadening. d Normalized MIR spectra with different pump wavelengths generated by OPG and cascaded process. e Normalized spectra generated by cascaded OPG-DFG. f Summary and comparison of PPLN, metasurface-assisted LN waveguide, and our nanophotonic waveguide in MIR.
