Fundamental-mode fiber-to-fiber coupling at high-power
2009 (English)In: Solid State Lasers XVIII: Technology and Devices, SPIE - International Society for Optical Engineering, 2009, 71930F- p.Conference paper (Refereed)
Fiber-to-fiber coupling between two different fibers is a state of the art technology. Products are available on the market where multimode fibers can be coupled with very low power loss, at very high powers (multi-kilowatt). We have, however, always been forced to accept a certain loss in beam quality, manifesting as an increase in the Beam Parameter Product (BPP). In fundamental-mode fiber-to-fiber coupling no beam quality is lost. We instead expect to have a certain power loss in the coupling. This paper addresses the problems in free-space fundamental-mode fiber-to-fiber coupling, including theoretical estimations of expected power loss, estimated demands on the stability of the optics as well as measured values on a fundamental mode fiber-to-fiber coupler. The theoretical calculations of the sensitivity of the coupling efficiency due to radial misalignment and defocus (longitudinal displacement) have been confirmed experimentally. Experimental results at 100 W laser power include 88% coupling efficiency using a large mode area fiber with mode-field diameter (MFD) of 18 μm and 75 % coupling efficiency using a single-mode fiber with MFD of 6.4 μm.
Place, publisher, year, edition, pages
SPIE - International Society for Optical Engineering, 2009. 71930F- p.
, Proceedings of SPIE - The International Society for Optical Engineering, ISSN 0277-786X ; 7193
Beam parameters, Fiber-to-fiber coupling, Fresnel transformation, Fundamental-mode, High-power
Other Engineering and Technologies
IdentifiersURN: urn:nbn:se:kth:diva-153601DOI: 10.1117/12.808192ISI: 000284870500010ScopusID: 2-s2.0-66749117823ISBN: 978-081947439-1OAI: oai:DiVA.org:kth-153601DiVA: diva2:753049
Solid State Lasers XVIII: Technology and Devices, 25 January 2009 through 29 January 2009, San Jose, CA, United States
QC 201410072014-10-072014-10-062014-10-07Bibliographically approved