Development of a Continuous Multi-Thousand Shot Electron Beam Pumped KrF Rep-Rate Laser for Fusion Energy

Abstract The Electra laser system is currently being developed at the Naval Research Laboratory to serve as a test bed for laser driver technologies needed for an inertial fusion energy power plant. The main amplifier has produced 730 J of laser light operating in an oscillator mode. These results as well as advancement of the laser physics, electron beam deposition, and the pulse power technologies give us projections of >7% wall plug efficiency for an IFE system. The Electra main amplifier in oscillator configuration has run continuously at 1 Hz, 2.5 Hz, and 5 Hz for multi-thousand shot runs. This paper will discuss recent results of the Electra program at the Naval Research Laboratory including integrating the Electra main amplifier into a complete laser amplifier system. Issues addressed will include development paths for the cathode, window coating, and foil longevity to attain the durability required for a fusion power plant.

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