Electronically Tunable Yb-Doped Mode-Locked Fiber Laser

We report a passively mode-locked picosecond Yb-doped fiber laser that is electronically tunable over 30 nm around 1.04 m. The fiber laser with a tuning accuracy of better than 0.1 nm and a tuning time of as fast as 15 s employs an acoustooptic filter. The semiconductor saturable absorber mirror used in a cavity with a frequency-shifted feedback improves noticeably the mode-locked operation.