We report on a novel ytterbium-doped fiber design which combines the advantages of rod and fiber gain media. The fiber design has the outer dimensions of a rod laser, meaning a diameter in the range of a few millimeters and a length of just a few ten centimeters, but including two important waveguide structures, one for the pump radiation and one for the laser radiation. 120 W output power in single-mode beam quality are obtained from a 48 cm long fiber cane, corresponding to an extracted power of 250 W per meter. The fiber has a significantly reduced nonlinearity and allowing therefore scalability of the performance of high peak power fiber laser and amplifier systems.
© 2005 Optical Society of AmericaPDF Article