140 W Cr:ZnSe laser system

We report a significant breakthrough in the development of fiber-pumped high-power CW laser systems based on Cr2+: ZnS and Cr2+: ZnSe gain media. We demonstrate output power levels of up to 140 W near 2500 nm, and 32 W at 2940 nm with corresponding optical efficiencies of 62% and 29%. Our novel approach is based on rapid simultaneous scanning of the collinear laser mode and pump beam across the Cr: ZnS/Se gain element which allows us to virtually eliminate thermal lensing effects and obtain unprecedented levels of output power with very high optical-to-optical efficiency. (C) 2016 Optical Society of America