Abstract

Double-clad rare-earth doped fiber lasers pumped by high brightness laser diodes are very efficient and compact sources of cw and pulsed radiation. Ytterbium-doped fiber lasers (YDFLs) have been demonstrated at around 1100 nm in cw configurations with output powers of 110 W¹ and in Q-switched operation with pulse energies approaching 10 mj.² Ytterbium can also emit at around 980 nm, with output power of around 1 W demonstrated in cw operation.³ Here, we present a Q-switched 980 nm cladding-pumped YDFL with 1.2 μj of energy and 60 W of peak power in pulses shorter than 20 ns at repetition rates of up to ~0.2 MHz and 250 mW of average output power for repetition rates between 0.2 and 0.65 MHz. A pulsed 980 nm source with high peak power and good beam quality is attractive for frequency conversion, e.g., frequency quadrupling to 245 nm.

© 2002 Optical Society of America