  In this work, the entanglement dynamics of a moving-biparticle system driven
by an external classical field are investigated, where the moving-biparticle
system is coupled with a zero temperature common environment. The analytical
expressions of the density operator and the entanglement can be obtained by
using the dressed-state basis when the total excitation number is one. We also
discuss in detail the effects of different parameters on the entanglement
dynamics. The results show that the classical driving can not only protect the
entanglement, but also effectively eliminate the influence of the qubit
velocity and the detuning on the quantum entanglement.
