342 µm lasing in heavily-erbium-doped fluoride fibers

~3.5 $\mu$ m Er3+: ZBLAN Fiber Laser in Dual-End Pumping Regime

“…Figure 3(a) depicts the average output powers as a function of the launched pump power of 1973 nm under different launched 976 nm pump powers. For P 976 nm=1.61 W there is a significant decrease of output power when the 1973 nm pump power goes beyond 3.2 W. The output power rollover can be attributed to the laser quenching effect that results from the non-resonant excited state absorption (ESA) of 1973 nm, which depletes ions on the upper laser level of the 3.5 µm transition and leads to the lack of ions in the virtual ground state ( 4 I 11/2 level) [24]. By increasing the launched 976 nm pump power, the 1973 nm pump power at which the output power begins to be quenched also increases.…”

“…They achieved a record output power of 5.6 W at 3.5 µm. Later on, they employed a dualend pumping regime in a heavily-erbium-doped fluoride fiber laser (erbium doping concentration of 7 mol.%), and realized 3.4 W laser emission at 3.5 µm [24]. Almost at the same time, H. Y. Luo et al also reported a watt-level gainswitched fiber laser at 3.5 µm based on a dual-end pumping scheme [25].…”

2.8 μm pulsed Er3+:ZBLAN fiber laser based on external gain modulation

“…This is a special case to directly modulate the laser photons through the saturable absorption effect with an additional pump. Recently, the successful demonstration of the ∼3.5 µm Er 3+ :ZBLAN fiber laser under the 976 nm and ∼2 µm dual-wavelength pumping regime greatly promotes its development in terms of the output power scaling, wavelength tuning range and the pulse shortening [25][26][27][28][29][30]. These results inspired us to further investigate the effect of the additional ∼2 µm pump on the ∼2.8 µm laser gain dynamics and the output temporal characteristics.…”

Generation of 2.8 µm fiber laser using an Erbium‐doped ZBLAN double‐clad fiber in a linear‐cavity‐free space experimental setup

“…24 In the recent years, few continuous wave fiber lasers operating in the wavelength of 2.7-4 µm have been reported using fluoride fiber doped with Er 3+ , Ho 3+ , and Dy 3+ . [25][26][27][28][29][30] However, the laser performance has limitation on output power and spectral width. Pulse fiber lasers could improve the pulse energy and spectral width of the laser.…”