Linearly polarized Q-switched pulse Yb fiber laser with average output power over 10 W

We report an acousto-optic (AO) Q-switched fiber laser with linearly polarized short pulse output. The fiber laser was set up by applying a piece of large mode area polarization maintaining Yb fiber of 1 meter length as the gain medium and a free-space AO Q-switch as the modulating element. The fiber laser was pumped by a fiber pigtailed laser diode working at 976 nm. By suitably adjusting the distance between the AO Q-switch and the cavity mirror, stable Q-switched short pulse laser output was achieved with output power up to 10 W and repetition rate between 20 kHz and 50 kHz. The shortest pulse duration of 33 ns was achieved at repetition rate of 20 kHz when the output power reached about 10 W. [GRAPHICS] Typical spectrum of the Q-switched fiber laser output emission showing FWHM of 10 nm around 1042 nm (C) 2009 by Astro Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA