KW Fiber Pump Combiner with Polarization Maintaining Feed Through

In this Phase I effort we plan to research and develop new methods, fixtures and processes for the fabrication of fused fiber components for high power fiber laser systems. We will initially focus on investigating, designing and testing new heat sources that provide a significant improvement in process control and are scalable to very large fiber bundles and very high pump powers. We will build sample 7:1 pump combiner using the newly developed heat sources, and test these combiners at pump power levels greater than 1kW to ensure the cleanliness of the fusion process. We will propose and model novel 6+1:1 feed-though combiner designs and fabrication processes that are applicable for high-power co- and counter-pumped configurations, including compatibility with polarization-maintaining (PM) large mode area (LMA) and photonic crystal (PCF) fibers operating at Yb or Tm wavelengths. BENEFIT: The completion of Phase I will provide the foundation for a Phase II effort that will lead to the development of novel glass processing equipment for the fabrication of very high-power optical fiber components and systems. This equipment will then be used in the research and development of bi-directional feed-through pump combiners for multi-kW fiber laser systems. There is a great potential military and commercial market for high power fiber lasers. Additionally, there is a smaller market potential for the fabrication equipment and components necessary to build these fiber laser systems.