2 µm actively Q-switched all fiber laser based on stress-induced birefringence and commercial Tm-doped silica fiber

• A 2 µm all-fiber Q-switched laser based on the stress-induced birefringence was demonstrated.
• A commercial Tm-doped silica fiber was proved to be capable of realizing stable Q-switched operation with this method.
• The repetition rates can be tuned from 25 to 175 kHz with the shortest pulse duration of 413.2 ns.

An actively Q-switched all-fiber laser operating at the wavelength of 1920 nm is experimentally demonstrated based on a readily accessible commercial Tm-doped silica fiber. The Q-switching is achieved by polarization modulation through the stress-induced birefringence using a piezoelectric transducer (PZT) as the Q-switcher. The pulsed fiber laser can be operated with the repetition rates ranging from tens of kilohertz to nearly two hundreds kilohertz with milliwatt average output power.