Abstract

Traditional active medium creation for short-wave lasers require a very intensive pumping (electron beams as a rule). Low effectiveness of coulomb's excitation at the interaction of such electrons with atoms being excited deals both with non-resonance character of the process and electron beams being used. We have shown for the first time that the excitation probability raised sharply at the excited medium being in a form of a thin oriented crystal plate (film). It occurs because a certain mutual orientation of a crystal target and electrons beam leads to a formation of movable quasi-atoms corresponding to channeling (in a crystal potential) electrons. At this the excitations process physically corresponds to a resonance process of excitation transmission from the movable quasi-atom (with its simaltaneous transition from the initial (e) to a finite (g) state) to a crystal atom (with a transition excitation 1 - 2). At the account of relativistic effects such a process allows to get an excited state with energy transition up to UV and X-ray ranges. Another reason of the grid atoms excitation process optimization is a self-focusing of channeling electrons in crystal regions directly adjacent to crystal planes having the most density of atom electrons. Both these factors, according to the calculations, raise the excitation probability of XUV and X-ray lasers active media (as compared with the case of non-oriented targets) in 10 times which allows to create similar lasers on the basis of moderately intensive channeling beams of relativistic electrons.

© 1996 IEEE