Dual-rod Yb:YAG laser for high-power and high-brightness applications

Abstract

We describe a diode-pumped Yb.YAG laser producing 1080 W cw with 27.5% optical-optical efficiency and 532 W Q-switched with M 2 =2.2 and 17% optical-optical efficiency. The laser uses two composite Yb.YAG rods separated by a 90 degree quartz rotator for bifocusing compensation. A microlensed diode array end-pumps each rod using a hollow lens duct for pump delivery. By changing resonator parameters, we can adjust the fundamental mode size and the output beam quality. Using a flattened gaussian intensity profile to calculate the modefill efficiency and clipping losses, we compare experimental data to modeled output power vs beam quality.