Effects of relaxation of electronic excitations from swift heavy ions in amorphous targets

Abstract

Swift heavy ions (SHIs) penetrating amorphous solids cause unusual phenomena that are not observed in crystals. For such ions the major contribution to the projectile energy loss comes from the excitation of electronic system of the target. The transition from the initial electronic excitations to structural modification and macroscopic changes in irradiated material involves a series of physical processes occurring on largely different time scales. These include excitation of electrons by a projectile, thermalization of the electronic subsystem, electron-to-ion energy transfer, relaxation of the excited material and the accompanying structural transformations. In this report this sequence of processes occurring in metallic amorphous solids is discussed and the current knowledge concerning the basic mechanisms involved is presented.