Thulium:Holmium-Co-Doped Fiber Lasers: Power Scaling and Long-Wavelength Emission

In this work, thulium:holmium-codoped fiber lasers are investigated as promising candidates for power scaling laser radiation in the long-wavelength 2 µm region. Based on a thorough examination and improvement of the laser setup, continuous-wave and nanosecond-pulsed lasers are built within the entire dedicated wavelength range from 2.09 µm up to 2.2 µm. As a potential application, the generated 2 µm radiation is used for nonlinear frequency conversion into the mid-IR.