Abstract

A 3 kilowatt level incoherently combined beam with 98% measured power transfer efficiency is demonstrated using an all-fiber Y-branch combiner. An M²factor of ≤3.5 was measured up to 600W. Transmitting the combined output through a specialty-core delivery fiber showed nearly brightness preserving performance. We used the same technology for a preliminary coherent combining, where it was shown to achieve a pure HE11 mode. This suggests an extremely high brightness beams can be achieved by using passive fiber combiners, while operating in the multi-kW regime.

© 2012 Optical Society of America