2 μm ultrafast fiber laser mode-locked by mechanically exfoliated Sb_2Te_3

摘要

We demonstrate the usage of a saturable absorber material - antimony telluride (Sb_2Te_3) for efficient mode-locking of a Thulium-doped fiber laser. The Sb_2Te_3 layers were obtained by mechanical exfoliation and transferred onto the fiber ferrule. The all-fiber laser was capable of generating optical solitons with the full width at half-maximum of 4.5 nm centered at 1945 nm, with 39.5 MHz repetition rate and more than 60 dB signal to noise ratio. The pulse energy of the generated 890 fs pulses was at the level of 30 pJ. Our experiment showed that Sb2Te3 saturable absorbers are suitable for the operation in 2 μm bandwidth.