Abstract

Erbium laser glasses have generated considerable interest because of their capability to emit eye-safe 1.54-µm laser radiation directly.^1,2 The relatively high threshold associated with the three-level laser system of Er³⁺ ion ⁴I_15/2-⁴I_15/2 transition and the low thermal-loading capability associated with typical laser glass materials have restricted the average output power of Er³⁺ glass lasers to a few watts. A new chemically strengthened phosphate laser glass, designated QX/Er, has been developed, which exhibits a high thermal-loading capability in combination with superior laser performance. The spectral properties of this new glass and the Q-switched, high-repetition-rate operation were reported^3,4 This paper describes our achievement of a laser with an average output power of 20 W at 1.54 µm and a slope efficiency of 4% based on our detailed investigation on pump dynamics, thermal behavior, and long-pulse laser performance of this new glass material. To our best knowledge, this is the most powerful and efficient lamp- pumped Er:glass laser to date.

© 1996 Optical Society of America