Entanglement Dynamics Between Two Atoms Within Different W-like Initial States

We investigate the entanglement dynamics between two atoms which are trapped in an optical cavity with the help of the concurrence and the negativity for two different kinds of normalized W-like initial states. The results show that one of them can suffer the so-called entanglement sudden death (ESD) depending on parameters of the initial state when the optical cavity in the vacuum state, while the other one does not for whatever parameters. However when the initial optical cavity photon number is nonzero, no matter what W-like state as atoms' initial state, the atoms' subsystem always undergoes the ESD phenomenon. Meanwhile, by comparing concurrence with negativity, we find that our model gives a concrete example to support the conclusions in the previous reference.