A Q-switched microchip laser generating 1064 nm wavelength, subnanosecond pulses at a 13.4 kHz repetition rate was used to seed a dual-stage amplifier featuring a 40 µm core Yb-doped photonic-crystal fiber (PCF) as the power amplifier. From this source, we obtained diffraction-limited (M2=1.05), ∼450 ps pulses of energy >0.7 mJ, peak power in excess of 1.5 MW, and an average power of ∼9.5W. By further amplifying the PCF output in a multimode 140 µm core Yb-doped fiber, we generated a peak power in excess of 4.5 MW, the highest obtained in a fiber source to our knowledge.
© 2005 Optical Society of America
Fiber Optics and Optical Communications
Fabio Di Teodoro and Christopher D. Brooks, "Multistage Yb-doped fiber amplifier generating megawatt peak-power, subnanosecond pulses," Opt. Lett. 30, 3299-3301 (2005)