ABSTRACT
The interaction of high-power laser radiation with matter produces plasma of varying characteristics. For solid targets the plasma produced in the blow-off is at a high temperature and relatively low density (in comparison with solid) whilst the shock generated by the ablation pressure moves into the target leaving material behind the shock front at relatively low temperature (for irradiances of < 1012 Wcm−2 this can be below the melting point of the solid) and higher than solid density. On the microscopic scale the variety of plasmas formed by high-power lasers presents great difficulty to the theorist who endeavours to provide a general model of plasma properties. For low temperature plasmas (at temperatures lower than the dissociation energy of the molecules involved) the microscopic description involves aspects of solid-state physics and plasma chemistry. At somewhat higher temperatures, which are considered in this lecture, the plasma involves only ions (potentially partially-ionised) and electrons, but even this simplification still results in great difficulty in the construction of a model of the microscopic physics involved.
