Frequency conversion of femtosecond laser pulses in an engineered aperiodic poled optical superlattice

Abstract

We theoretically propose a procedure based on a cascading genetic algorithm for the design of aperiodically quasi-phase-matched gratings for frequency conversion of optical ultrafast pulses during difference-frequency generation. By designing the sequence of a domain inversion grating, different wavelengths at the output idler pulse almost have the same phase response, so femtosecond laser pulses at wavelength 800 nm can be shifted to other wavelengths without group-velocity mismatch.

Continuous ultraviolet to blue-green astrocomb

“…While simple devices typically employ a constant , sophisticated control over the wavelength conversion properties can be obtained by spatially varying along the propagation direction. Analytic calculation 40 , simulated-annealing 41 and genetic algorithms 42 can be used to design gratings where the length of each crystalline domain contributes to the realization of particular wavelength conversion outcome optimized for spectral shape and efficiency.…”