3 µm Q-switched Er³⁺:ZBLAN laser with V₄AlC₃ saturable absorber

We report a Q-switched Er³⁺:ZBLAN fiber laser based on Vanadium Aluminum carbide (V₄AlC₃) as a saturable absorber (SA). Our SA is fabricated by depositing V₄AlC₃ nanoparticles on a gold mirror to form an SA film. The proposed laser operates at the 2784.32 nm central wavelength with a 1.68 nm 3 dB bandwidth. The maximum pulse energy and output power are 3.51 µJ and 490 mW at a maximum pump power of 6.6 W. To the best of our knowledge, this is the first time that V₄AlC₃ provides Q-switching in the 3 µm region. The proposed SA is promising for mid-infrared pulsed lasers.