High power fiber lasers

High power fiber lasers are one of the hot topics in laser science and technology in recent years. The clad pumping of double clad fiber lasers was the key issue for high power performance in the last decade. The clad pumping scheme demonstrated more than 100 W from a single core fiber. A new concept of high power fiber lasers, a fiber disk laser, was developed in Japan in the middle of the 90s. The fabrication technique of fiber embedded disk was developed in a cooperation program supported by Japanese government. We report the concept of high power fiber lasers under development in Japan.