Soliton ultrafast fiber laser with V₄AlC₃ MAX phase in 2 µm region

We demonstrate a mode-locked thulium-doped fiber laser (TDFL) using a new vanadium aluminum carbide (V₄AlC₃) as a saturable absorber (SA). Using the embedding method, we prepared a thin film containing V₄AlC₃ powders into polyvinyl alcohol (PVA). SA film was placed in a TDF laser cavity to produce a mode-locked laser. The mode-locked TDFL was operating at 1976.2 nm with a 3 dB bandwidth of 3.44 nm, respectively. At the input power of 850 mW, the laser generated the maximum output power of 12.2 mW, a pulse duration of 1.65 ps, a repetition rate of 34.65 MHz, a signal-to-noise ratio of 57 dB, and a pulse energy of 0.35 nJ. To our knowledge, this is the first time utilizing V₄AlC₃ PVA as SA to produce pulses in the 2-μm region.