@article{Aydin:17,
author = {Yigit Ozan Ayd{i}n and Vincent Fortin and Fr\'{e}d\'{e}ric Maes and Fr\'{e}d\'{e}ric Jobin and Stuart D. Jackson and R\'{e}al Vall\'{e}e and Martin Bernier},
journal = {Optica},
keywords = {Infrared and far-infrared lasers; Lasers, erbium; Lasers, fiber; Fiber Bragg gratings ; Femtosecond fiber lasers; Fiber lasers; High power fiber lasers; Light wavelength; Multimode lasers; Single mode lasers},
number = {2},
pages = {235--238},
publisher = {OSA},
title = {Diode-pumped mid-infrared fiber laser with 50\% slope efficiency},
volume = {4},
month = {Feb},
year = {2017},
url = {http://www.osapublishing.org/optica/abstract.cfm?URI=optica-4-2-235},
doi = {10.1364/OPTICA.4.000235},
abstract = {Until now, the field of mid-infrared fiber laser research has been constrained by the limitation imposed by the Stokes efficiency limit. The conversion of high-power diode light emission operating at near-infrared wavelengths into mid-infrared light invariably results in the deposition of significant amounts of heat in the fiber. This issue is compounded by the fact that mid-infrared transmitting glasses are thermomechanically weak, which means scaling the output power has been a longstanding challenge. In this report, we show that by cascading the adjacent transitions of the erbium ion at 2.8 and 1.6 $\mu$m in combination with a low-loss fluoride fiber, the slope efficiency for emission at 2.8 $\mu$m can reach 50\%, thus exceeding the Stokes limit by 15\%. We also show that by highly resonating the 1.6 $\mu$m transition, a highly non-resonant excited-state absorption process efficiently recycles the excitation back to the upper laser level of the mid-infrared transition. This demonstration represents a significant advancement for the field that paves the way for future demonstrations that will exceed the 100 W power level.},
}