Glass-clad single crystalline fiber lasers
Journal
Proceedings of SPIE - The International Society for Optical Engineering
Journal Volume
8381
Date Issued
2012
Author(s)
Lai, C.C.
Hsu, K.Y.
Huang, C.W.
Jheng, D.Y.
Wang, S.C.
Lin, S.L.
Yang, M.H.
Lee, Y.W.
Huang, D.W.
Abstract
Yttrium aluminium garnet (YAG) has been widely used as a solid-state laser host because of its superior optical, thermal, mechanical properties, as well as its plurality in hosting active ions with a wide range of ionic radii. Drawing YAG into single crystalline fiber has the potential to further scale up the attainable power level with high mode quality. The recent advancement on the codrawing laser-heated pedestal growth (CDLHPG) technique can produce glass-clad YAG crystalline fibers for laser applications. The drawing speed can reach 10 cm/min for mass production. The CDLHPG technique has shown advantages on transition-metal ion doped YAG and short-fluorescent-lifetime ion doped YAG host. Compared to silica fiber lasers, the crystalline core offers high emission cross section for transition metal ions because of the unique local matrix. The challenges on the development of glass-clad YAG fibers, including core crystallinity, diameter uniformity, dopant segregation, residual strain, post-growth thermal treatment, and the thermal expansion coefficient mismatch between the crystalline core and glass clad are discussed. Chromium, ytterbium, and neodymium ions doped YAG fiber lasers have been successfully achieved with high efficiency and low threshold power. Power scaling with a clad-pump/side-coupling scheme using single clad or double clad YAG fibers is also discussed.
SDGs
Type
conference paper