Harmonic generation and frequency upconversion in Pr3+-doped germanosilicate optical fibers pumped at 1.319 μm

Abstract We report on the generation of visible light signals through harmonic generation and frequency upconversion in Pr 3+ -doped germanosilicate single-mode optical fibers pumped by a Q -switched and modelocked Nd:YAG laser operated at 1.319 μm. Growth rate of the frequency-doubling process seeded by upconversion fluorescence signal and instantaneous efficient frequency-tripling is also demonstrated.