AN EFFICIENT PHOTO-ATOM SOURCE
E.Mariotti, M.Meucci, P.Bicchi, C.Marinelli, L.Moi
We show that it is possible to obtain a very efficient photo-atom source, whose atom flux is regulated by light. The atom release is due to the recently observed light-induced atom desorption effect from silane coated cells. We report the results obtained at room temperature with rubidium in a double body cell coated with (poly)dimethyl-siloxane. This kind of photo-atom source can be immediately extended to other alkali atoms, namely sodium, potassium and cesium. Possible applications are discussed.
PACS codes and keywords: 32.80, 42.50 (Photon interactions with atoms, Quantum Optics; Surface physics)
Published in Optics Communications 134 (1997) 121
LIGHT INDUCED ATOM DESORPTION: A PHOTO-ATOMIC EFFECT
E.Mariotti, L.Moi
The effect of non resonant and weak light on the adsorption-desorption processes of alkali atoms on organic coated surfaces is discussed and a new phenomenon, the light-induced atom desorption, is presented. It is demonstrated that light can control the adsorption-desorption as well as the diffusion of the atoms inside silane coatings.
Published in "Quantum Optics of Confined Systems" M.Ducloy and D. Bloch eds., Kluwer Academic Publisher (Les Houches 1996) 355
DYNAMICS OF RUBIDIUM LIGHT INDUCED ATOM DESORPTION (LIAD)
E.Mariotti, S.N.Atutov, M.Meucci, P.Bicchi, C.Marinelli, L.Moi
Rubidium desorption induced by weak and non resonant light has been observed in a siloxane coated cell. The effect is non-thermal and produces a huge variation of the vapor density at room temperature. This effect has been observed, for the first time, by A.Gozzini et al.with sodium upon similar conditions. The dynamics of this new effect is here discussed and the desorption-adsorption rates are measured.
Published in Chemical Physics 187 (1994) 111-115
LIGHT INDUCED ATOM DESORPTION
M.Meucci, E.Mariotti, P.Bicchi, C.Marinelli, and L.Moi
In the present paper we report experimental evidence of a new effect,observed for the first time by A.Gozzini et al. on sodium vapor, in which an important rubidium vapor density increase (larger than one order of magnitude) is observed when siloxane-coated cells are shined by non-resonant and weak light. The effect is due to non-thermal light-induced atom desorption. A preliminary analysis of its dependence on the light power density and on the wavelength has been carried out.
Published in Europhysics Letters 25(9) (1994) 639-643
LIGHT INDUCED DIFFUSION AND DESORPTION OF ALKALI METALS IN A SILOXANE FILM:
THEORY AND EXPERIMENT.
S.N.Atutov , V.Biancalana, P.Bicchi, C.Marinelli, E.Mariotti, M.Meucci, A.Nagel, K.A.Nasyrov, S.Rachini, and L.Moi
Light induced desorption and diffusion of alkali atoms in organic films are new and interesting fields of investigation. An impressive demonstration of it is given by the recently observed LIAD effect, where a huge alkali atom desorption from siloxane films, previously exposed to atomic vapours, is induced by weak and non-resonant light. In this paper new experimental data and a 1-D theoretical model of the effect are presented. The model gives a good descritpion of the vapour density dynamics by taking into account both the atomic diffusion inside the coating and the surface desorption. General equations are reported and discussed within the limits of experimental interest. The potential barrier at the vapour-surface interface and the activation energy for Rb in (poly)dimethylsiloxane have been determined.
PACS 34.50.Dy, 79.20.La
Published in Phys.Rev.A 60, p.4693 (1999)
A NEW CLASS OF PHOTO-INDUCED PHENOMENA IN SILOXANE FILMS
C. Marinelli, K.A. Nasyrov#, S. Bocci, B. Pieragnoli, A. Burchianti, V. Biancalana, E. Mariotti, S.N. Atutov#, L. Moi
INFM-UdR Siena, Dipartimento di Fisica - Università di Siena
Via Banchi di Sotto 55, 53100 Siena , Italy
# permanent address: Institute of Automation and Electrometry, Novosibirsk, Russia
The light induced atomic desorption effect, known as LIAD, is observed whenever Pyrex cells, coated with siloxane films and containing alkali atoms, are illuminated. LIAD is a non-thermal phenomenon and it can be observed even with very weak light intensities. We show that the simultaneous contribution to the photo - emission of atoms adsorbed both at the film surface and within the film must be taken into account in order to fit the experimental data. We demonstrate that both the desorption efficiency and the diffusion coefficient of the alkali atoms embedded in the dielectric film depend on the desorbing light intensity. These features characterize a new class of photo-induced phenomena whose analysis gives new insights in the comprehension of the atom-surface interaction and of the atom-bulk diffusion and opens interesting perspectives for applications.
PACS 34.50.Dy, 79.20.La
