Decoherence and entanglement in radiative decay of a diatomic system

It is shown that, in the Markov approximation, relaxation of two noninteracting atoms in the field of a common thermostat leads not only to decoherence but also to the opposite process of the entanglement of atomic states, which can take on a stationary value depending on the initial conditions. This region of initial conditions narrows as the mean number of photons in the thermostat increases. The main radiative mechanism destroying an arbitrary initial entanglement of atoms is interaction of each atom with its own thermostat independent of the other. All Markov relaxation models under consideration are based on the Lindblad equations.