SOLID-STATE LUMINESCENCE - PROBE FOR ION-SOLID INTERACTIONS

We have observed the light emission from CsI films, at room temperature, induced by single H-, low-mass organic, and CsI negative ions in the 2045-keV energy range. The light signal was studied using wavelength and time-resolved analysis in order to probe the energy-transfer process between keV ions and target atoms. Prompt-decay photon yields are found to be proportional to the energy deposited into the electronic system of the target directly through electronic stopping and indirectly via the collision cascade. Photons are attributed to the luminescence of self-trapped excitons. Solid-state luminescence may be useful in probing the interactions between projectile and target in the time interval between the impact and the sputtering of surface species. © 1995 The American Physical Society.