Materials processing applications using multi-kilowatt free-electron lasers

Summary form only given.Previous work using ultrafast lasers has shown improvements in the cutting and drilling of materials, compared to lasers in common use, but a barrier to their commercial use is the limited average power available, which makes the cost/photon prohibitively high. Some applications, such as the surface processing of polymers or metals, require laser powers of the tens of kilowatts, and therefore are not yet commercial processes. However the development of FELs based on superconducting RF linac technology provides a scalable path to laser outputs above 50 kW, rendering these applications economically viable, since the cost/photon drops as the output power increases. Such FELs will provide quasi-cw (PRFs in the tens of MHz), of ultrafast (/spl sim/1 ps) output with very high beam quality. The first example of such an FEL is the IR Demo FEL, which produces nearly 2 kW of high average power on a routine basis. Housed in a multilaboratory user facility, we have started materials process studies. I present some of the first results of these studies. I also briefly discuss the status of our project to upgrade the FEL to 10 kW in the mid IR.