Generation of coherent short-wavelength radiation --- High-order harmonics and x-ray lasers

Sammanfattning: The recent availability of short-pulse, high-intensity, compact lasers has opened doors to new and fascinating areas in atomic physics. Using the Lund Terawatt Laser, the interaction of femtosecond, near-infrared and visible laser radiation with matter at intensities in the range 10¹³--10¹⁷ W/cm2 was studied. Out of many phenomena that occur in this intensity range, this thesis deals with two: the short-wavelength amplification of the spontaneous emission in plasmas created from solid and gas targets, and the generation of high-order harmonics of the fundamental laser frequency. Both phenomena can serve as a basis for the generation of short-wavelength, coherent radiation, which is of great interest in many scientific and industrial applications.