DEMONSTRATION OF A DISCHARGE PUMPED TABLE-TOP SOFT-X-RAY LASER

We report the first observation of large soft-x-ray amplification (gl = 7.2) in a discharge-created plasma. A fast, similar to 40 kA, curren t pulse from a compact discharge was used to excite plasma columns up to 12 cm in length in 4-mm channels, producing population inversion in the J = 0-1 line of Ne-like Ar and resulting in a gain of 0.6 cm(-1) at 46.9 nm. The beam divergence was measured to be <9 mrad.