208-W TEM00 operation of a diode-pumped Nd : YAG rod laser

208-W average-power TEM00-mode operation from a diode-pumped Nd:YAG rod las er was demonstrated. The side-pumping method of generating a high-gain aber ration-free rod, the bifocusing-compensation technique with two identically pumped rods, and a suitable choice of beam spot size were employed in the design of this laser. At the maximum pump power of 1.1 kW the fundamental t ransverse-mode operation (M-2 < 1.1) was characterized by 7.6% electrical e fficiency. The extraction efficiency was almost 60% of full multimode opera tion. Stable operation was obtained within a pump-power range of 15% of the maximum pump power. (C) 1999 Optical Society of America OCIS codes: 140.34 80, 140.3530.