Harmonics Generation in Ultra-Thin Nanofilms Irradiated by Intense Nonrelativistic Short Laser Pulse

The problem of harmonics generation in nanotargets is considered at the range of parameters (a nanotarget diameter and a pump laser intensity) when the oscillation amplitude of an electron in a target is much larger than the target width. Electron motion in charged nanotargets in the presence of a laser field of different (non-relativistic) strength is considered. It is demonstarted that for lasers of infrared frequencies clusters do not posess strong enough potential to bound electrons with large oscillation amplitudes. Opposite to clusters, nanofilms were found to be very perspective targets in the problem considered. A simple analytic model and molecular dynamic simulations showed increased harmonics generation when the oscillation amplitude of electrons in a film becomes much larger, than the film width. Different regimes of generation are briefly discussed.