Studies on passively Q-switched ytterbium doped all-fiber laser using fiber optic ring resonator

We report our studies on ytterbium doped fiber laser passively Q-switched by fiber optic ring resonator in all-fiber format. The Q-switched laser characteristics viz. pulse duration, pulse profile, repetition rate and average power are easily varied not only by pump power but also by changing the polarization state of light inside the laser resonator with the help of polarization controllers. At 330 mW pump power, the laser generates 1.07 mu s duration pulses with 0.68 mu J pulse energy at 83.6 kHz repetition rate. The Q-switched laser wavelength is tunable from 1059 to 1069.7 nm by changing the polarization state inside the cavity.