Tunable dual-wavelength actively Q-switched Er/Yb double-clad fiber laser

We demonstrate experimentally a dual-wavelength tunable actively Q-switched fiber laser using 3 m of Er3+/Yb3+ co-doped fiber as the gain medium. For wavelength tuning we used a tunable Hi-Bi FBG having two reflection wavelengths separated by 0.4 nm. The laser emits a dual-wavelength signal that is tunable in a range of 11.8 nm. Laser operation can be switched between single and double wavelength emission. The laser operates at repetition rates from 30 to 110 kHz with pulse durations of 280 ns and pulse energies near 0.5 μJ.