| High-intensity, laser-matter interactions result in the generation of short-wavelength radiation through a number of mechanisms. In this work, the generation of coherent, short-wavelength radiation from a variety of such interactions will be discussed.;When focused into a gas, high-intensity lasers may produce cold, dense non-equilibrium plasmas. These plasmas may undergo rapid recombination and collisional cascade to form a population inversion and, therefore, gain on an inner-shell transition of plasma ions. The experimental and theoretical investigation of such a recombination-pumped laser system is reported in this work. The laser operates at 135 A on the Ly-;Another type of coherent radiation generated in a high-intensity, laser-matter interaction is high order harmonic radiation. When focused onto either solid or gas targets high-intensity lasers have been shown to generate a burst of radiation at harmonics of the laser frequency. This work reports the first demonstration of high order harmonics generated from small clusters of atoms. We show that such microclusters exhibit a stronger non-linear response to the laser field than conventional gas targets, and that this non-linearity allows the microclusters to produce harmonics of a higher energy than is possible in a comparable conventional gas target. |
