Photo-ejection and transport of alkali atoms embedded in nano-porous silica

Recently we observed non-thermal photoejection of atoms embedded in nano-porous silica samples. Alkali atoms are stored inside porous glass matrices and then they are desorbed by ordinary or laser light. In this paper, we present an experimental investigation of the dependence of photodesorption dynamics on desorbing radiation, showing that light induced effects on alkali nano-particles, dispersed in the glass matrix, are started up upon specific conditions of the incident radiation. On the basis of this study, we find that the light is able both to drive the atomic flux from the glass surface and to modify the optical properties of the glass samples, opening interesting perspectives for applications.