Analysis of picosecond-pulse wavelength conversion based on cascaded sum-frequency generation and difference-frequency generation in quasi-phase-matched <inline-formula><math altimg="none" display="inline" overflow="scroll"><mrow><mi mathvariant="normal">Li</mi><mi mathvariant="normal">Nb</mi><msub><mi mathvariant="normal">O</mi><mn>3</mn></msub></mrow></math></inline-formula> waveguides Conferences