High-power wavelength-tunable photonic-crystal-fiber-based oscillator-amplifier-frequency-shifter femtosecond laser system and its applications for material microprocessing

• Published in: Laser physics letters Vol. 6; no. 1; pp. 44 - 48
• Main Authors: Liu, B.-W., Hu, M.-L., Fang, X.-H., Wu, Y.-Z., Song, Y.-J., Chai, L., Wang, C.-Y., Zheltikov, A.M.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.01.2009; WILEY‐VCH Verlag; Wiley
• Subjects: femtosecond laser technologies; photonic-crystal fibers; ultrafast optics
• ISSN: 1612-2011; 1612-202X
• DOI: 10.1002/lapl.200810084

A high‐power wavelength‐tunable femtosecond fiber laser source is developed based on photonic‐crystal fiber technology. Laser oscillator and amplifier stages in this system employ diode‐pumped ytterbium‐doped single‐polarization large‐modearea photonic‐crystal fibers in a stretcher‐free configuration, delivering laser pulses with an average power of 10.4 W, a pulse width of 52 fs, and a peak power of 4 MW at a repetition rate of 50 MHz after pulse compression. Nonlinear transformation of such laser pulses in a highly nonlinear photonic‐crystal fiber yields light pulses smoothly tunable within the range of wavelengths from 1.0 to 1.4 μ m and allows the generation of supercontinuum stretching from 450 to at least 1750 nm. We report experiments on silicon microprocessing and chromium nanofilm patterning at a high repetition rate, demonstrating the potential of the developed fiber‐laser source for fast micromachining, microfabrication, and microprocessing. (© 2009 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA)