9 - Strong Field Interactions with Overdense Plasmas

Summary

Intense irradiation of solid targets creates an overdense plasma surface which absorbs and reflects incident laser radiation, the subject of this final chapter. Following a survey of the physics of the plasma formation, heat transport and hydrodynamic expansion, the range of effects that absorb the laser energy are each considered, starting with collisional absorption, followed by detailed exploration of collisionless absorption mechanisms including resonance absorption, vacuum heating and JxB heating. The hot electron production and transport that accompanies these absorption mechanisms is explored, followed by assessment of ponderomotive force effects on the plasma surface, with steepening and hole-boring physics elucidated. The reradiation of high harmonic emission from the plasma surface is discussed in the context of the oscillating mirror model. The acceleration of ions from solid targets is then described with particular attention given to the target normal sheath acceleration mechanism. Why and how strong magnetic fields are produced by intense irradiation of solid-target plasmas are answered and some integrated phenomena resulting from all of this physics is surveyed.