Sudden Death and Long-Lived Entanglement Between Two Atoms in a Double JC Model System

Abstract

Considering a double JC model with different coupling constants, we investigate the entanglement between the two two-level atoms, and discuss dependence of the atomatom entanglement on the different coupling constants, and the detuning between the atomic transition frequency and the cavity field frequency. The results show when = δ/g is small, with the increase of the relative difference of the two atom-cavity coupling constants γ , the atom-atom entanglement periodically evolves with the amplitude slowly and periodically modulated. What's more interesting is that long-lived entanglement between the two atoms can be obtained when atom A non-resonantly interacts with the cavity field a, and atom B has no coupling with the cavity field b. In this case, the concurrence C AB (t) of the two atoms evolves in form of cosine, and is invariant and equals the initial value when far off resonance. In addition, we find that the so-called entanglement sudden death can occur under appropriate conditions on the detunings and the different coupling constants for different initial atomic states.

Population inversion and entanglement in single and double glassy Jaynes-Cummings models

“…In Fig. 12, we can see that there are sudden deaths of entanglement, followed by revivals, for both the cases when G A = G B [16,17,21,[23][24][25] and when G A is slightly different from G B [19,20,24]. Here, by the phrase "sudden death", it is meant that entanglement vanishes at a point in time in such a way that its derivative is discontinuous there.…”

“…The behavior of entanglement in the time dynamics of an initially entangled state when the dynamics is governed by the double JC Hamiltonian has been studied before. In particular the G A = G B case was studied in [16,17,21,[23][24][25] and the G A = G B case in [19,20,24]. Here, we assume ω = ν for simplicity, but keep G A = G B , in general, and study the response of atom-atom entanglement in time-evolved state to quenched disordered atom-cavity couplings.…”

“…The phenomenon of entanglement sudden death (ESD) was observed in the double JC model in [17,18]. For further studies, see [19][20][21][22][23][24][25][26].…”

Entanglement and Fisher Information for Atoms–Field System in the Presence of Negative Binomial States

“…The entanglement phenomenon of sudden death in the double JCM was observed [ 14 ]. For further studies, see [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. Since the JCM is considered an ideal in the context of quantum optics, its extension has been considered, such as in the case of a single-mode field with multi-level atoms and the Tavis–Cummings model [ 23 , 24 , 25 , 26 , 27 , 28 ].…”

Quantum Discord of Two Atoms Interacting with a Single-mode Thermal Field

“…Yet, entanglement is very sensitive to the system-environment interaction and the initial state of the system. When considering an initial entangled state exposed to local noisy environments, the entanglement may decrease abruptly and nonsmoothly to zero in a finite time, which is called entanglement sudden death (ESD) [5][6][7][8]. However, recent researches have shown that even fully separable, highly mixed, states can contain intrinsically quantum correlations and these could offer a valuable resource for quantum computation [9][10][11][12].…”