A Simple Demonstration of Q-Switched Bismuth Doped Fiber Laser at 1722 NM

We demonstrate a Bismuth (Bi)-doped fiber laser (BDFL) that generates pulses through passive Q-switching. Stable Qswitching operation was attained, with the shortest pulse width of 0.5 µs, and a tunable repetition rate ranging from 51 to 89 kHz. These results provide evidence that a simple configuration employing a commercially available semiconductor saturable absorber (SESAM) is suitable for the pulsed operation of BDFL in the 1700 nm region and offers potential for further development.