Entanglement evolution of two remote and non-identical Jaynes-Cummings atoms
Abstract
A detailed treatment of the entanglement dynamics of two distant but non-identical systems is presented. We study the entanglement evolution of two remote atoms interacting independently with a cavity field, as in the double Jaynes-Cummings (JC) model. The four-qubit pairwise concurrences are studied, allowing for asymmetric atom-cavity couplings and off-resonant ineractions. Counter to intuition, imperfect matching can prove advantageous to entanglement creation and evolution. For two types of initial entanglement, corresponding to spin correlated and anti-correlated Bell states and , a full, periodic and directed transfer of entanglement into a specific qubit pair is possible, for resonant interactions, depending on the choice of relative couplings. Furthermore, entanglement transfer and sudden death (ESD) can be prevented using off-resonant interactions, although for some initial states, detunings will trigger an otherwise frozen entanglement, to allow a full entanglement transfer. We confirm a conservation rule governing the pairwise entanglement between the non-interacting systems, that for the initial state the sum of the square of these concurrences (SSC) is conserved. For , the total SSC is reduced periodically, even to zero in some cases, to reveal a complete and abrupt loss of all non-local pairwise entanglement.