We report here on a practical, cryogenically cooled cw laser. The laser consists of a multiply sensitized Ho:YLF laser rod cooled by circulating liquid nitrogen and optically pumped by a 1000W tungsten halogen lamp. An output of 35W with a slope efficiency greater than 4% has been obtained from a 5 mm diameter by 60 mm long laser rod. The laser is continuously tunable over a 20 nm range around 2.06 μm.
© 1984 Optical Society of AmericaPDF Article