Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:quant-ph/0606182 · Physical Review A

Quantum interference and evolution of entanglement in a system of three-level atoms

Łukasz Derkacz, Lech Jakóbczyk

Published Sep 14, 2006• 63 citations
arXivHTMLPDF

Abstract

We consider a pair of three-level atoms interacting with the vacuum. The process of disentanglement due to spontaneous emission and the role of quantum interference between principal transitions in this process, are analyzed. We show that the presence of interference can slow down disentanglement. In the limit of maximal interference, some part of initial entanglement can survive.

DOI
10.1103/physreva.74.032313

Related papers

Local aspects of disentanglement induced by spontaneous emission

Anna Jamróz

We consider spontaneous emission of two two-level atoms interacting with vacuum fluctuations. We study the process of disentanglement in this system and show the possibility of changing disentanglement time by local unitary operations.

arXiv:quant-ph/0602128•Journal of Physics A Mathematical and General•May 31, 2006•54 citations

Protecting bipartite entanglement by quantum interferences

Sumanta Das, G. S. Agarwal

We show that vacuum-induced coherence in three-level atomic systems can lead to preservation of bipartite entanglement when two such atoms are prepared as two initially entangled qubits, each independently interacting with their respective vacuum reservoirs. We explicitly calculate the time evolution of concurrence for two different Bell states and show that a large amount of entanglement can survive in the long time limit. The amount of entanglement left between the two qubits depends strongly on the ratio of the nonorthogonal transitions in each qubit and can be more than $50%$. Moreover, we find that as a consequence of vacuum-induced coherence, sudden death of entanglement is prevented for an initial mixed entangled state of the qubits.

arXiv:1004.0564•Physical Review A•May 28, 2010•37 citations

Vacuum-induced stationary entanglement in radiatively coupled three-level atoms

Łukasz Derkacz, Lech Jakóbczyk

We consider a pair of three-level atoms interacting with a common vacuum and analyse the process of entanglement production due to spontaneous emission. We show that in the case of closely separated atoms collective damping can generate robust entanglement of the asymptotic states.

arXiv:0710.5048•Journal of Physics A Mathematical and Theoretical•Apr 30, 2008•13 citations

Dynamical evolution and protection of entanglement between atoms coupled with electromagnetic vacuum fluctuations

Anwei Zhang

The dynamical evolution of entanglement between two polarizable two-level atoms in weak interaction with electromagnetic vacuum fluctuations is investigated. We find that, for initial Bell state $\psi^{\pm}$, the decay rate of entanglement between atoms is just the superradiant spontaneous emission rate, which depends not only on the spontaneous emission rate of atom but also on the modulation of the spontaneous emission rate due to the presence of another atom. It is shown that, with the presence of a boundary, the entanglement between transversely polarizable atoms can be protected for a very long time. It is pointed out that when the two atoms in initial Bell state $\psi^{-}$ are put close enough , the entanglement between them can also be protected.

•Dec 1, 2016•0 citations

Comment on “Protecting bipartite entanglement by quantum interferences”

Anjali N. Nair, R. Arun

In an interesting article [Phys. Rev. A 81, 052341 (2010)], Das and Agarwal have discussed the preservation of bipartite entanglement in three-level atoms employing the coherences induced by spontaneous emission. The authors considered various initially entangled qubits prepared from two $\mathsf{V}$-type three-level atoms and showed that more than $50%$ of the initial (bipartite) entanglement can be preserved in steady state due to vacuum-induced coherence. In this Comment, we point out that their analytical formulas for the entanglement measure contain errors affecting all the numerical results of that article. We substantiate our claim by giving correct analytical results for the time evolution of the two-atom system.

Physical Review A•Mar 15, 2018•4 citations

Spontaneous emission from a three-level atom

Shi-Yao Zhu, Ricky C. F. Chan, Chin Pang Lee

Quantum interference between decay processes from two upper levels, which are coupled by the same vacuum modes to a lower level, have been investigated and its effects on the spontaneous emission spectrum have been studied. The interference can result in spectral narrowing and a black dark line in the spectrum. The population in the upper levels is not a simple exponential decay due to the interference.

Physical Review A•Jul 1, 1995•214 citations
We consider a pair of three-level atoms interacting with the vacuum. The process of disentanglement due to spontaneous emission and the role of quantum interference between principal transitions in this process, are analyzed. We show that the presence of interference can slow down disentanglement. In the limit of maximal interference, some part of initial entanglement can survive.
We show that vacuum-induced coherence in three-level atomic systems can lead to preservation of bipartite entanglement when two such atoms are prepared as two initially entangled qubits, each independently interacting with their respective vacuum reservoirs. We explicitly calculate the time evolution of concurrence for two different Bell states and show that a large amount of entanglement can survive in the long time limit. The amount of entanglement left between the two qubits depends strongly on the ratio of the nonorthogonal transitions in each qubit and can be more than 5050%50. Moreover, we find that as a consequence of vacuum-induced coherence, sudden death of entanglement is prevented for an initial mixed entangled state of the qubits.
The dynamical evolution of entanglement between two polarizable two-level atoms in weak interaction with electromagnetic vacuum fluctuations is investigated. We find that, for initial Bell state ψ±\psi^{\pm}ψ±, the decay rate of entanglement between atoms is just the superradiant spontaneous emission rate, which depends not only on the spontaneous emission rate of atom but also on the modulation of the spontaneous emission rate due to the presence of another atom. It is shown that, with the presence of a boundary, the entanglement between transversely polarizable atoms can be protected for a very long time. It is pointed out that when the two atoms in initial Bell state ψ−\psi^{-}ψ− are put close enough , the entanglement between them can also be protected.
In an interesting article [Phys. Rev. A 81, 052341 (2010)], Das and Agarwal have discussed the preservation of bipartite entanglement in three-level atoms employing the coherences induced by spontaneous emission. The authors considered various initially entangled qubits prepared from two V\mathsf{V}V-type three-level atoms and showed that more than 5050%50 of the initial (bipartite) entanglement can be preserved in steady state due to vacuum-induced coherence. In this Comment, we point out that their analytical formulas for the entanglement measure contain errors affecting all the numerical results of that article. We substantiate our claim by giving correct analytical results for the time evolution of the two-atom system.