A cw diode-pumped single-silica fiber comprising 40 cores used as active elements for a high power fiber laser at /spl lambda/=1050 nm

Summary form only given. We have introduced a multicore fiber used as gain medium for a fiber laser. Nearly 40 monomode cores are fitted into a standard multimode silica glass fiber laser serving as the pump radiation transport fiber. The cores are arranged on an annulus situated next to the border of the fiber. The multimode fiber guides the pump radiation by which the Nd(3+)-doped cores are excited.