Stutzki, FabianFabianStutzkiJansen, FlorianFlorianJansenLiem, AndreasAndreasLiemJauregui, CesarCesarJaureguiLimpert, JensJensLimpertTünnermann, AndreasAndreasTünnermann2022-03-042022-03-042012https://publica.fraunhofer.de/handle/publica/22819710.1364/OL.37.0010732-s2.0-84858606741We demonstrate a Q-switched fiber laser system emitting sub-60 ns pulses with 26 mJ pulse energy and near-diffraction-limited beam quality (M2<1.3). In combination with a repetition rate of 5 kHz, a corresponding average output power of 130 W is achieved. This record performance is enabled by a large-pitch fiber with a core diameter of 135 µm. This fiber allows for effective single-mode operation with mode field diameters larger than 90 µm even at average output powers exceeding 100 W.en620535journal article