Lasing at 7.9 nm in nickellike neodymium

Using a series of 150-ps pulses from the Nova laser to illuminate neodymium slab targets, we observe a 38-psduration lasing pulse at 7.906 nm in nickellike neodymium on the J = 0 ? 1, 4d ? 4p transition. To overcome the low gain in this system, we used a traveling-wave geometry in conjunction with two slab targets that were coupled lengthwise to increase the effective length and whose surfaces were curved to compensate partially for refraction effects.