Calculation of decoherence rate for atom-field interaction in induced-emission processes

In deceherence theory it is emphasized that the interaction between quantum systems and their environment is responsible for the emergence of classical properties through quantum substrates. Mathematically, decoherence is defined as the practically irreversible disappearance of certain nondiogonal elements from the density matrix of a bounded but open systems. The concept and dynamical aspects of decoherence in induced-emission processes are analysed while their consequences on atom-field interactions are discussed.