Diode-side-pumped Nd:YLiF_4 laser emitting at 1053 nm with 53.6% optical efficiency and diffraction-limited beam quality

摘要

We present a Nd:YLiF_4 diode-side-pumped resonator architecture based on a gain-guided, mode-selective technique that employs a double pass of the fundamental laser mode through the crystal. The folded cavity is very compact, robust and cost efficient. With this design we demonstrate 19 W of quasi-cw, stable diffraction-limited laser emission at 1053 nm when pumping at 792 nm with 35.4 W. The slope efficiency of the laser is 65.3% and the optical-to-optical efficiency is 53.6%, which is, to the best of our knowledge, the highest efficiency reported for Nd:YLiF4 lasers pumped into the ~4F_(5/2) band, including longitudinal pumping schemes and lasers emitting at the higher gain line of 1047 nm.