Low repetition rate broadband high energy and peak power nanosecond pulsed Yb-doped fiber amplifier

We demonstrate a broadband fiber amplifier system emitting 10 nm pulses with 33 mj pulse energy at repetition rates between 1 and 20 Hz. In combination with a pulse width of 10 ns, a corresponding peak output power over than 3 MW was achieved. This record performance was enabled by fiber with core diameter of 200 mu m. Furthermore, in order to suppress amplified spontaneous emission (ASE), multistage pulse pump technology was applied and different pumping characteristics had been measured. Finally, 15% extraction efficiency was obtained when output energy reached 33 mJ. Output capability of the amplifier was not limited by SBS and ASE but the pump peak power. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.