Next Generation Large Mode Area Fiber Technologies for High Power Fiber Laser Arrays.

摘要

This program has successfully accomplished its main objective in that large core single-mode Ge-doped and Yb-doped CCC fibers have been developed as a platform for monolithically-integrated building blocks (individual laser channels) of high power beam-combined fiber laser arrays. Robust single-mode performance of CCC fibers with core sizes of up to approximately 60m has been rigorously demonstrated. Various CCC fiber based high power lasers have been also demonstrated, including 600W SBS-free single-frequency linearly-polarized cw fiber MOPA system, mJ pulsed and high-pwer ultrashort-pulse CPA systems. Accurate numerical modeling tools for designing CCC structures have been developed. Fabrication of CCC fibers reached such a degree of maturity that they have become available commercially. Furthermore, this program resulted in a successful demonstration of SBS suppression in acoustic-guidance tailored fibers with up to 13dB SBS threshold increase, which to our knowledge constitutes one of the largest SBS suppression achieved to date. UUIC group also performed an extensive study of SBS gain coefficient magnitude and spectrum in a variety of fiber glass materials.