High Power Pump Couplers for High Energy Fiber Lasers

We propose to develop a novel pump energy coupler for high power fiber lasers. The overall goal of this program is to deliver a multi-kilowatt fiber laser system based on the high efficiency coupling technique. High power diode power injection into the inner cladding of active fibers has been a bottleneck for multi-kilowatt fiber lasers. The new coupler will be compatible with any pumping wavelength. The advantages of the new technique will include high wall-plug pump efficiency, brightness preservation, distributed pump injection and good heat dissipation. This proposed project is a moderate risk and high reward effort. The risk is moderate because detailed demonstration of the concept must be made although the theoretical study and preliminary laboratory research have set in place a significant foundation for the proposed effort. The reward is high because the success of the program will eliminate a major obstacle in current fiber laser development. The enabling technology will also benefit other diode pumped solid-state lasers, and provide couplers for researchers to develop new fiber lasers.