Abstract

We report on the first realization of efficient x-ray lasers using transient gain in collisionally excited neon-like ions. These lasers are working on a double pulse excitation scheme proposed by us in 1993 [1] for solid and foil targets.In a first step, a long ns- pump pulse produces a plasma column of the desired neon-like ions with both a uniform electron density and temperature.The second but short ps- pump pulse arrives at the preformed plasma after a certain delay and heats it up very rapidly, producing very efficiently a transient gain. Lasing was experimentally realized on the 3p-3s transitions in Titanium XII at 32.6 nm, as well as in Vanadium XIV at 30.4 nm. Additionally, in Ti a bright lasing line at 29.8 nm was recorded, which is supposed to result from a photo pumped 3d-3p transition.

© 1996 Optical Society of America