X-ray generation by electron photo-recombination in charged atomic clusters formed in intense femtosecond laser pulses

Abstract

The new mechanism of x-ray generation by clusters at their irradiation by femtosecond laser pulses has been suggested. We develop photo-recombination theory for electrons which first leave atomic clusters due to the outer ionization and then go into the ground quantum state of the neighbouring charged cluster. The charged cluster field is considered as a quantum potential well. The conclusion has been made that non-dipole x-ray photons at the photo-recombination into charged clusters have an energy which is larger than that for the well-known photo-recombination on separate atomic ions inside the cluster.

Electronic oscillations in ionized sodium nanoclusters

“…As mentioned above, this method leads to bigger computational noise that particularly may result in multiple peaks near the plasma frequency (see figrue 2 in [22]). Moreover, the relation of this spectra to σ ω ( ) seems to miss ω 2 (see equation (7) in [22]) as the correct equation reads σ ω βΩ ω = ω P P ( ) ; 0 2 el el . In our view this is the most likely reason for the discrepancy although a more comprehensive comparison of these computational methods is to be done.…”

“…Nanometer-sized atomic and molecular clusters (nanoclusters) have been studied extensively for the last few decades due to their unique properties. From a practical point of view they provide enhanced laser absorption compared to a bulk matter resulting in creation of effective x-ray or particle beam sources [1][2][3][4][5][6][7] used for various applications such as ionography [8]. On the other hand experimental studies of nanoclusters facilitate elaboration of the theory of finite size quantum and classical systems [9].…”