  We investigate the creation of entanglement between two quantum emitters
interacting with a realistic common stationary electromagnetic field out of
thermal equilibrium. In the case of two qubits we show that the absence of
equilibrium allows the generation of steady entangled states, which is
inaccessible at thermal equilibrium and is realized without any further
external action on the two qubits. We first give a simple physical
interpretation of the phenomenon in a specific case and then we report a
detailed investigation on the dependence of the entanglement dynamics on the
various physical parameters involved. Sub- and super-radiant effects are
discussed, and qualitative differences in the dynamics concerning both creation
and protection of entanglement according to the initial two-qubit state are
pointed out.
