Ferroferric-oxide nanoparticle based Q-switcher for a 1 μm region

Transition metal oxides (TMOs) have been successfully demonstrated as Q-switchers for pulsed fiber lasers. In this work, the ferroferric-oxide (Fe3O4) nanoparticles are synthesized via chemical co-precipitation. Filmy Fe3O4/polyvinyl alcohol (PVA) is adopted as a Q-switcher in the 1 mu m region. The Fe3O4/PVA film has the modulation depth of 7.8% and saturable intensity of 71.32 MW/cm(2), respectively. By incorporating the Fe3O4/PVA film into Yb-doped fiber laser (YDF) cavity as a saturable absorber (SA), the stable Q-switching operation is obtained in 77-157 mW pump power range. At the pump power of 147 mW, the Q-switched YDF laser emits stable laser pulses with the maximum single pulse energy of 50.35 nJ and shortest pulse duration of 1.63 mu s. The experimental results indicate that the zero-dimensional Fe3O4 nanoparticles have a bright prospect for nonlinear optics applications. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement