111 kW (0.5 mJ) pulse amplification at 1.5 μm using a gated cascade of three erbium-doped fiber amplifiers

Abstract
The generation of high peak power pulses by amplification of the output from a distributed feedback diode laser is demonstrated using a cascade of three erbium‐doped fiber amplifiers (EDFAs) separated by an acousto‐optic gate. The optimized amplifier chain consisted of two high efficiency single‐mode EDFAs pumped with 40 mW at 980 nm, followed by a multimode EDFA pumped with 1.5 W at 978 nm. At low repetition rates, peak output powers of 111 kW and energies of 0.5 mJ at 1.534 μm were obtained.