We report a high-power, high-efficiency continuous-wave Tm:KY(WO4)2 (Tm:KYW) laser based on multimode in-band diode pumping at 1720 nm. In-band pumping reduces the quantum defect compared to conventional 800-nm pumping, enabling efficient high-power operation. We demonstrate up to 4.55 W of output power near 1.94 µm with a slope efficiency of 83% with respect to absorbed pump power, approaching the quantum-defect limit. The laser provides smooth wavelength tunability from 1839 to 2100 nm and maintains near-diffraction-limited transverse beam quality across the full operating range. These results indicate that multimode in-band pumping of Tm:KYW is a simple and compact route to efficient, broadband, high-power sources in the 1.9–2.0 µm region, providing a practical basis for future high-power Q-switched and mode-locked systems.
Trawi et al. (Mon,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: