High-energy Q-switched ytterbium-doped all-fiber laser with tris-(8-hydroxyquinoline) aluminum as saturable absorber

We have experimentally demonstrated a Q-switched fiber laser operating in the 1 mu m region by using tris-(8-hydroxyquinoline) aluminum (Alq(3)) as a saturable absorber (SA). The Alq(3) was fabricated through a drop-casting technique, where the material was embedded into a polyvinyl alcohol (PVA) film so that it can effectively incorporated into a laser cavity. The fiber laser has produced a high pulse energy of 0.8 mu J and peak power of 90 mW. When the laser cavity was reduced from 25 m to 5 m, the peak power increased and the pulse energy dropped to 237.62 mW and 451.5 nJ, respectively. Additionally, the minimum pulse width was reduced from 9 mu s to 1.9 mu s. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement