Müller, M.M.MüllerKienel, M.M.KienelKlenke, A.A.KlenkeGottschall, T.T.GottschallShestaev, E.E.ShestaevPlötner, M.M.PlötnerLimpert, J.J.LimpertTünnermann, A.A.Tünnermann2022-03-052022-03-052016https://publica.fraunhofer.de/handle/publica/24564410.1364/OL.41.003439An ultrafast fiber chirped-pulse amplifier comprising eight coherently combined amplifier channels is presented. The laser delivers 1 kW average power at 1 mJ pulse energy and 260 fs pulse duration. Excellent beam quality and low-noise performance are confirmed. The laser has proven suitable for demanding scientific applications. Further power scaling is possible right away using even more amplifier channels.en535journal article