Spontaneous emission of an atom near a wedge F. S. S. Rosa Los Alamos National Laboratory Work in collaboration with T.N.C. Mendes, C. Farina and A. Tenorio

Plan of the talk Introduction The method An atom inside a wedge The spontaneous emission rate Final remarks

Introduction “A splendid light has dawned on me about the absorption and emission of radiation.” A. Einstein QED (1927) :

Spontaneous emission and boundary conditions - Theory P.W. Milonni and P.L. Knight (1973), M.R. Philpott (1973). G. Barton (1970), P. Stehle (1970), Parallel polarization Normal polarization

Experiments Feher et al. (1958) - microwave range Drexhage et al. (1968) - visible range An experiment on suppression - Jhe et al. (1987) Conducting plates Oven Beam of atoms Detector

The results

The method We use a master equation approach developed by Dalibard, Dupont-Roc and Cohen-Tannoudji to describe a particle (in our case, an atom) interacting with a reservoir (the radiation field). This approach provides general expressions for the atomic energy shifts and the exchange rates.

Using some reasonable approximations for the master equation, we get transition rate energy shift

Some important expressions } } = =

An atom inside a wedge R

The wedge has been used for some important measurements of the van der Waals force. It is the most soft departing from the plane geometry, and its relative simplicity allows some analytical calculations. To use an alternative method that gives expressions valid in both retarded and non- retarded regimes. Some Motivations

The excited potential

Graphic results  =  /3  =  /5  =  /8

The spontaneous emission rate

Graphic results

From another perspective

Suppressed emission y /  =  /3 PP NP

 =  /8  =  / PP NP

Final remarks Everything seems to be working fine for the wedge setup. Refine our investigation: introduce temperature and finite conductivity effects. Investigate the possibility of trapping particles using the vacuum field.