High efficiency operation of Tm:Y2O3 ceramic laser in-band pumped at 1620 nm

Abstract

We report on high power and efficient laser operation of low scattering loss Tm:Y₂O₃ ceramic fabricated in house via coprecipitation process. The Tm³⁺ ion is pumped directly to the upper energy level of the ~ 2 μm laser transition (³F₄ → ³H₆) using a high power 1620 nm fiber Raman laser. With an optically polished but uncoated sample of 2 at.% doping, the laser generated 11.3 W of TEM₀₀ output power at ~2050 nm for ~19 W of absorbed pump power, corresponding to a slope efficiency of 74.4% with respect to absorbed pump power.