Reliable 20W CW operation of 880 nm laser arrays with aluminum-free active regions

Summary form only given. It has been predicted that direct upper-state pumping of Nd:YAG and Nd:YVO/sub 4/ at 885 nm and 880 nm would yield lower threshold and better slope efficiency as compared to traditional pumping at 808 nm (Lavi et al., 1999; Lavi and Jackel, 2000). Models also predict /spl sim/40% reduction in heat load for direct upper-state pumping compared to pumping at 808 nm. This is important for high power CW operation, where maximizing efficiency and minimizing heat generation is critical. In this work, we report the performance and reliability of compact 20W CW diode bars suitable for this direct upper-state pumping application.