Dynamical creation of entanglement versus disentanglement in a system of three-level atoms with vacuum-induced coherences

Abstract

The dynamics of entanglement between three -level atoms coupled to the common vacuum is investigated. We show that the collective effects such as collective damping, dipole -dipole interaction and the cross coupling between orthogonal dipoles, play a crucial role in the process of creation of entanglement. In particular, the additional cross coupling enhances the production of entanglement. For the specific initial states we find that the effect of delayed sudden birth of entanglement, recently invented by Ficek and Tanaś [Phys. Rev. A 77, 054301(2008)] in the case of two -level atoms, can also be observed in the system. When the initial state is entangled, the process of spontaneous emission causes destruction of correlations and its disentanglement. We show that the robustness of initial entanglement against the noise can be changed by local operations performed on the state.

Quantum correlations as precursors of entanglement

“…This has important consequences for the dynamical behavior of the system. A common environment may entangle initially separable systems, even in the absence of direct interaction [37][38][39][40][41][42][43][44][45][46][47]. This can be easily understood from the fact that the product state |0 |⊗|1 may be expressed as a sum of a singlet and a triplet component:…”

Qutrit geometric discord

“…Quantum dynamics of collective systems of such atoms significantly differ from a dynamics of two-level atoms (see e.g. [2][3][4]). On the other hand, the theory of quantum correlations between the pairs of such atoms is much more complex than in the case of qubits.…”

Distillability sudden death and sudden birth in a two-qutrit system under decoherence at finite temperature

“…On the contrary, when an initially prepared in bound entangled or separable state becomes a distillable entangled state in a finite time, then it is said that it undergoes distillability sudden birth [22]. Recently great attention has been paid to the development of works on distillability sudden death [23][24][25][26][27][28][29][30] and sudden birth [31][32][33] addressing the practical problems of environmental decoherence. For example, Mazhar Ali investigated distillability sudden death of two-qutrit systems in the presence of either collective or multilocal noises [23,24].…”