Abstract. We summarize the progress achieved at LSAI in the understanding and optimization of the transient collisional pumping of x-ray lasers using an ultra-short picosecond heating pulse. A strong ×300-400 enhancement of the 13.9 nm Ni-like 4d-4p lasing emission is obtained when a travelling-wave short pulse irradiates the preformed plasma. The temporal history of the 13.9 nm laser pulse is measured with a high-resolution streak camera. A very short, 2 ps x-ray laser pulse is directly demonstrated for the first time.

Keywords: x-ray lasers, transient pumping, travelling wave, nickel-like ions, collisional excitation

Print publication: Issue 11 (November 2001)
Received 18 April 2001, in final form 22 August 2001, accepted for publication 3 September 2001
Published 9 October 2001