Atomic sources controlled by light: main features and applications

We present in this paper recent results on Light-Induced Atom Desorption (LIAD) in sealed and open coated cells. LIAD is defined via the description of an experiment on rubidium atoms stored in a dry - film coated cell, where a few milliwatts of even non coherent and non resonant light are able to increase the alkali atomic density for more than one order of magnitude. Modeling of the effect is given. New features become relevant in the case of LIAD in porous glasses: in fact, although the photodesorption efficiency per unit area in bare glass is much lower, photoatomic sources can be prepared, due to the huge inner surface of porous samples. We applied LIAD from organic coatings to the stabilization of alkali densities out of equilibrium: sodium case is here discussed. Finally, we report on fully original, preliminary measurements of rubidium Magneto - Optical Trap loading via LIAD from a dry - film coated cell.