A Single-Longitudinal-mode Er:YAG Laser and MOPA System Based on the Faraday Effect

We demonstrate a continuously operating Er:YAG single-longitudinal-mode laser and its amplifier with a corner cube retroreflector based on the Faraday effect. A maximum power of 1.02 W, the central wavelength of 1645.46 nm, Er:YAG single-longitudinal-mode laser with a line-width of 204 kHz has been realized. The slope efficiency is 9.38% and the beam quality factors M2 are 1.16, 1.05 in the x and y directions. Additionally, the singlelongitudinal-mode laser is amplified to 1.86 W by the double-pass amplifier. The results indicate that the unidirectional operation ring laser in combination with the corner cube prism provides a 1.6 & mu;m continuous-wave single-longitudinal-mode laser with high-power and stability.