High-power neodymium glass laser systems for fusion research

One of the key issues of scientific feasibility experiments for fusion research is to construct a laser energy driver delivering enough output power for implosion. We have constructed a series of glass laser systems: Gekko II silicate glass laser (two-beam) 0.4 TW, Gekko IV phosphate glass laser (four-beam), 4 TW, and modules of Gekko XII, which will achieve 40 TW at full size. Laser glass is critical for delivering a large amount of power in a short duration without deterioration of the beam quality. Phosphate and fluorophosphate glasses have been investigated for an advanced laser design. Optical components have been developed which are expected to be very reliable. A system performance of lasers is also very important for experimental work.