Passively $Q$ -Switched Red Pr 3+ -Doped Fiber Laser With Graphene-Oxide Saturable Absorber

In this letter, a compact Q-switched red (635.7 nm) praseodymium (Pr3+)-doped fluorozirconate fiber laser using graphene-oxide (GO) as a saturable absorber (SA) is demonstrated experimentally. Furthermore, a silica fiber end coated with a dielectric film was employed to construct the compact resonator. The laser possesses a wide range of pulse repetition rate from 64.1 to 195.3 kHz and the minimum...