Gaida, C.C.GaidaStutzki, F.F.StutzkiGebhardt, M.M.GebhardtHeuermann, T.T.HeuermannBreitkopf, S.S.BreitkopfEidam, T.T.EidamRothhardt, J.J.RothhardtLimpert, J.J.Limpert2022-03-152022-03-152020https://publica.fraunhofer.de/handle/publica/41192310.1364/ASSL.2020.AW5A.1We present the first coherently combined, thulium-doped fiber CPA delivering >100 W average-power and simultaneously >1 GW of peak-power. Incorporating four amplifier channels the laser delivers pulses with >228 µJ energy and <120 fs duration at 1940 nm center wavelength. Excellent long-term stability is achieved with an average power fluctuation of <0.5% RMS over >48 hours - ideal prerequisites for next-generation industrial and scientific applications.en620conference paper