Top-hat beam output with 100 μJ temporally shaped narrow-bandwidth nanosecond pulses from a linearly polarized all-fiber system.

We report on an all-fiber system delivering more than 100 μJ pulses with a top-hat beam output in the few nanoseconds regime at 10 kHz. The linearly polarized flattened beam is obtained thanks to a 3-mm-long single-mode microstructured fiber spliced to the amplifier’s output.