Compact dual-crystal Tm,Ho:YLF laser with balanced orthogonal polarization output power

Power balanced orthogonally polarized dual-wavelength Ho:GdVO4 laser with a difference frequency of 1 THz

A power balanced orthogonally polarized dual-wavelength Ho:GdVO₄ laser was demonstrated for the first time. Without inserting any other devices into the cavity, the power balanced simultaneous orthogonally polarized dual-wavelength laser at π-polarization 2048nm and σ-polarization 2062nm was successfully achieved. At the absorbed pump power of 14.2 W, the maximum total output power was 1.68 W, and the output powers of 2048nm and 2062nm were 0.81 W and 0.87 W, respectively. The interval between the two wavelengths in the orthogonally polarized dual-wavelength Ho:GdVO₄ laser was nearly 14nm, corresponding to the frequency separation of 1 THz. This power balanced orthogonally polarized dual-wavelength Ho:GdVO₄ laser can be applied to generate the terahertz wave.

High power and efficient operation of a Ho:Y2O3 ceramic laser with over 210 W of output power at 2.1 µm

We report on power scaling and efficient operation of a Ho:Y₂O₃ ceramic laser at 2.1 µm in-band pumped with an incoherently beam combined high power and narrow-linewidth Tm fiber source at 1931.2 nm. The 0.5 at.% Ho³⁺ doped Ho:Y₂O₃ ceramic is fabricated in-house with scattering loss of < 0.25% cm^-1. Up to 210.5 W of continuous-wave output power has been generated at 2117 nm for 366 W absorbed pump power shaped with a one-dimensional top-hat profile, corresponding to a slope efficiency of 60.0% with respect to the absorbed pump power. A slope efficiency of 67.5% has been demonstrated with 160 W of output power using a circular beam pump configuration. Results presented in this work verify the superior power scaling capability of a Ho:Y₂O₃ ceramic laser with high efficiency at ∼2.1 µm.