Abstract

Yb:YAG and several other Yb-doped crystals have been demonstrated to lase efficiently [1]. Recently, Yb³⁺ in glass host materials have also attracted much attention especially because of the smaller reabsorption at the laser wavelength and the much smoother spectra compared to Yb:YAG. The used Yb:fluoride phosphate glass was developed at the University of Jena. An interesting feature of this glass is the higher absorption cross section at 973 nm (σ_a = 1.2 × 10⁻²⁰ cm²). The Yb:fluoride phosphate glass was doped with 5 × 10²⁰ cm⁻³ Yb³⁺ and exhibits a fluorescence lifetime of 1.2 ms Laser performance of this glass has been impressively demonstrated with a slope efficiency of 55% and a maximum cw output power of 460 mW by longitudinal pumping with a Ti:sapphire laser [2].

© 1996 IEEE