title: High-power tandem pumped fiber amplifier with an output power of 2.9 kW.
abstract: We report on a high power fiber amplifier tandem pumped by an industrial style thin-disk laser. An output power of 1 kW and a very good slope efficiency of 73% have been obtained for a state-of-the-art photonic crystal fiber originally designed for short-pulse amplification. We also compare this result to an experiment, where a power of 2.9 kW could be obtained from a step-index large-mode-area fiber with the same slope efficiency.
authors.affiliation: Fraunhofer Institute for Applied Optics and Precision Engineering, Albert-Einstein Strasse 7, 07745 Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Wirth
authors.forename: Oliver
authors.initials: O
authors.lastname: Schmidt
authors.forename: Andrea
authors.initials: A
authors.lastname: Kliner
authors.forename: Thomas
authors.initials: T
authors.lastname: Schreiber
authors.forename: Ramona
authors.initials: R
authors.lastname: Eberhardt
authors.forename: Andreas
authors.initials: A
authors.lastname: Tünnermann