Mode-locked 2μm fiber laser with a Tm/Ho-doped fiber saturable absorber

A mode-locked 2 μm fiber laser with a simple ring cavity is experimentally demonstrated. By inserting the Tm/Ho-doped fiber saturable absorber into a laser cavity pumped by a 793 nm diode laser, a stable mode-locked pulse at a central wavelength of 2010.11 nm was obtained. The repetition rate, maximum average output power, 3 dB spectral bandwidth, pulse width, and signal-to-noise ratio are 3.76 MHz, 9.63 mW, 0.16 nm, 28.2 ns, and 37 dB, respectively. To the best of our knowledge, this is the first reported mode-locked 2 μm fiber laser using a Tm/Ho-doped fiber saturable absorber.