Stable and Efficient Pulsed Mid-Infrared Laser Generation from an Er3+-Doped ZBLAN Fiber Laser

Abstract

We demonstrate a stable and efficient passively Q-switched 2.8 μm Er3+-doped ZBLAN fiber laser with a broadband semiconductor saturable absorber mirror. Enabled by the broadband optical modulator, the stable Q-switched fiber laser can deliver a maximum average power over 700 mW with corresponding per-pulse energy of 8.19 μJ and a pulse width of 1.3 μs at a repetition rate of 88.6 kHz under an incident pump power of 3.8 W. In addition, the slope efficiency can reach 22.5%. To the best of our knowledge, this is the highest reported slope efficiency for the passively Q-switched Er3+-doped ZBLAN fiber laser.