Phosphate laser glasses (review)

A review is given of the structure of phosphate glasses, thermooptic distortions in laser active elements, dependence of the thermooptic properties on the phosphate glass composition, and nonlinear optical characteristics of the glasses. An analysis is made of the criteria governing changes in the structure, spectral-luminescence, and lasing characteristics of the glasses in systems utilizing monovalent and bivalent metal metaphosphates with different additives. A comparison is made between the lasing parameters of phosphate and silicate glasses activated with Nd³⁺ ions. Data are given on excitation energy transfer processes in phosphate glasses, and on the spectral-luminescence and lasing properties of phosphate glasses activated with Yb³⁺+Er³⁺ and Nd³⁺+Yb³⁺ ions. The potential usefulness of phosphate glasses in different laser systems is demonstrated.