LAUSR

We demonstrate multi-stage ytterbium-doped fiber amplifiers (YDFAs) seeded with a superluminescent light emitting diode (SLED). Laser pulses with four pulse durations, such as 350-ps, 6-ns, 55-ns, and 183-ns (full width half maximum), have been studied. The peak powers reach 332, 95, 119, and 92 kW for the four types of laser pulses, respectively. The 350-ps laser pulses are generated through gain switching. Thanks to the broadband optical spectrum of the seed laser from the SLED, the stimulated Brillouin scattering is avoided. The configuration of such YDFAs seeded by an SLED with adjustable laser pulse durations (from picosecond to nanosecond) is desirable for many industrial applications.