All-fiberized polarized mode-locked thulium-doped fibre laser

We present an all-fiberized polarized mode-locked thulium-doped fibre laser system operating at the 2 μm region. Passively mode-locking by a semiconductor saturable absorber mirror, the laser generated 20.2 ps pulses at a repetition rate of 10.22 MHz. The maximum average output power of 56 mW with pulse energy of 5.48 nJ was achieved, and the output beam was more than 99.6% linearly polarized. To the best of our knowledge, it is the first mode-locked polarized thulium-doped fibre laser with all-fiberized configuration.