Interaction processes between photons and atoms

The recent spectacular developments in electromagnetic radiation sources (lasers, masers, synchrotron radiation sources) has led to a renewed interest in the interaction processes between photons and atoms. The authors review the different elementary interaction processes (absorption, scattering, emission and photons exchange) and give a detailed account of more complex phenomena like multi-photons processes, radiative relaxation, Rabi oscillation. The authors have gathered in this book different theoretical approaches (the pilot equation for particles, the Langevin equation, the Bloch optical equations) that are, for some, more adapted to the description of a particular kind of interaction than others. Different methods such as the perturbative method, the partial resummation method and the method of the 'dressed' atom are presented and illustrated with simple applications. (A.C.)