Abstract

The interaction of very short laser pulses with matter has become an important field.^1,2)If a pulse duration of a laser light is so short that no significant hydrodynamic expansion of a matter takes place, the electric field of a laser interacts directly with a solid density matter. The mean ion distance, a~ (3/4πn_i)^1/3is of the order of one angstrom at a solid density. The quivering distance of electrons oscillating at a laser frequency, ${\text{δx=eE}}_{\text{0}}/{\text{mω}}_0^2$, exceeds the mean ion distance at a high intensity. In addition to that, the ion coupling coefficient, Γ=eϕ/kt=z²e²/akt, is of the order of one for such high density plasma. Thus the oscillating electrons interact with many ions and electrons at the same time, because ions and electrons are also strongly correlated.

© 1989 Optical Society of America