Highly efficient Ho: YAP laser with 202 W of linearly polarized output power at 2118 nm

Abstract

We report on high power and efficient operation of a compact Ho: YAP laser in-band pumped at 1931 and 1943 nm with a high-power and narrow-linewidth Tm-doped fiber laser. Using a 0.5at. % Ho3+ doped Ho: YAP cut along the b-axis and a simple two-mirror resonator, up to 202 W of output power has been generated at ∼2118 nm for 336 W of absorbed pump power at 1931 nm, corresponding to a slope efficiency of 61.2% with respect to the absorbed pump power. The laser output is linearly polarized along the c-axis with a polarization extinction ratio (PER) of ∼20.0 dB. Results presented in this work verify the superior power scaling capability of Ho: YAP at ∼2.1 μm with high lasing efficiency.

Studying the Absorption and Fluorescence Parameters of Ho: YAP Laser Using the Judd-Oflet Model

“…It requires knowing the density (ρ (ion/cm 3 )) of the Holmium ion of the sample under study. The density can be calculated through the following Equation (16) :…”

“…Using (Beer-Lambert's law), the absorption coefficients of the model at these wavelengths were also calculated. The absorption cross-section can be calculated by substituting K(v) (calculated from the emission spectrum of the model) into the following equation (16,26) :…”

“…When (A spo ) represents the probability that spontaneous emission will occur; as a result of the effect of the electrode dipole compound, it is (16) :…”

High power Er:YAP laser at 2.92 μm based on incoherent beam combining

“…The work reported here not only boosts the average power of Er: YAP lasers, but also provides a feasible scheme for the power scaling of MIR solid-state lasers with linearly polarized output such as Ho:YLF lasers and Ho:YAP lasers. 28,29) (a) (b)…”