Research on the all-solid-state passively mode-locked laser with Fe3O4 nanosheets saturable absorber

Ferroferric-oxide nanoparticles(FONP) are a novel saturable absorber(SA) that have been demonstrated in passively mode-locked laser. Recently, our group developed a large-scale Ferroferric-oxide nanosheet(FONS) using a self-assembly method induced by a magnetic field. In this study, large-size FONS were prepared by self-assembly method under magnetic field induction and characterized under microscope, SEM and I-scan system and used for the first time in solid-state passively mode-locking as a saturable absorber. Using this novel saturable absorber in Nd:YVO4 laser, a mode-locked laser with a pulse duration of 506 ps at a repetition rate of 110 MHz at the wavelength of 1064 nm was achieved. The average output power and single pulse energy of the mode-locked laser are 165 mW, 50 nJ, up to 385 mW, 117 nJ.