Considering the dynamics of a two-qubit entangled system in the decoherence environment, we investigate the stability of pairwise entanglement under decoherence. We find that for different decoherence models, there exists some special class of entangled states of which the pairwise entanglement is the most stable. The lifetime of the entanglement in these states is larger than other states with the same initial entanglement. In addition, we also investigate the dynamics of pairwise entanglement in the ground state of spin models such as Heisenberg and $XXY$ models.Considering the dynamics of a two-qubit entangled system in the decoherence environment, we investigate the stability of pairwise entanglement under decoherence. We find that for different decoherence models, there exists some special class of entangled states of which the pairwise entanglement is the most stable. The lifetime of the entanglement in these states is larger than other states with the same initial entanglement. In addition, we also investigate the dynamics of pairwise entanglement in the ground state of spin models such as Heisenberg and $XXY$ models.

arXiv:quant-ph/0507021Physical Review AAug 12, 200513 citations

Entanglement, Coherence and Decoherence

José Antonio Fornés

Springer series in biophysicsJan 1, 20240 citations

DECOHERENCE, PURIFICATION AND ENTANGLEMENT

E. C. G. Sudarshan

Solvay Conference on PhysicsAug 1, 20031 citation

Decoherence-Induced Sudden Death of Entanglement and Bell Nonlocality

Dong-Gil Im, Yoon-Ho Kim

Decoherence due to the unwanted interaction between a quantum system and environment leads to the degradation of quantum coherence. In particular, for an entangled state, decoherence makes a loss of entanglement and Bell nonlocality known as entanglement sudden death (ESD), and Bell nonlocality sudden death (BNSD). Here, we theoretically investigate the entanglement and Bell nonlocality of a bipartite entangled state under three types of decoherence, amplitude damping, phase damping, and depolarizing. Our result provides the bound of decoherence strength that does not lose the entanglement and Bell nonlocality. In addition, we find two interesting features. One is that the entanglement can survive even though one of the entangled qubits is affected by a large strength of decoherence if the other qubit is affected by a small enough strength of decoherence except for the depolarizing. The second one is that when a specific form of entangled state is under amplitude damping, the Bell nonlocality shows an asymmetric behavior respect to the decoherence strengths on each qubit. Our work provides comprehensive information on ESD and BNSD for the bipartite entangled state which will be useful to implement quantum information processing in the presence of decoherence.Decoherence due to the unwanted interaction between a quantum system and environment leads to the degradation of quantum coherence. In particular, for an entangled state, decoherence makes a loss of entanglement and Bell nonlocality known as entanglement sudden death (ESD), and Bell nonlocality sudden death (BNSD). Here, we theoretically investigate the entanglement and Bell nonlocality of a bipartite entangled state under three types of decoherence, amplitude damping, phase damping, and depolarizing. Our result provides the bound of decoherence strength that does not lose the entanglement and Bell nonlocality. In addition, we find two interesting features. One is that the entanglement can survive even though one of the entangled qubits is affected by a large strength of decoherence if the other qubit is affected by a small enough strength of decoherence except for the depolarizing. The second one is that when a specific form of entangled state is under amplitude damping, the Bell nonlocality shows an asymmetric behavior respect to the decoherence strengths on each qubit. Our work provides comprehensive information on ESD and BNSD for the bipartite entangled state which will be useful to implement quantum information processing in the presence of decoherence.

PhotonicsJan 24, 20226 citations

Decoherence of entangled kaons and its connection to entanglement measures

Reinhold A. Bertlmann, Katharina Durstberger-Rennhofer, Beatrix C. Hiesmayr

We study the time evolution of the entangled kaon system by considering the Liouville--von Neumann equation with an additional term which allows for decoherence. We choose, as generators of decoherence, the projectors to the two-particle eigenstates of the Hamiltonian. Then we compare this model with the data of the CPLEAR experiment and find in this way an upper bound on strength $\ensuremath{\lambda}$ of the decoherence. We also relate $\ensuremath{\lambda}$ to an effective decoherence parameter $\ensuremath{\zeta}$ considered previously in literature. Finally we discuss our model in the light of different measures of entanglement, i.e., von Neumann entropy S, entanglement of formation E, and concurrence C, and we relate decoherence parameter $\ensuremath{\zeta}$ to the loss of entanglement: $1\ensuremath{-}E.$We study the time evolution of the entangled kaon system by considering the Liouville--von Neumann equation with an additional term which allows for decoherence. We choose, as generators of decoherence, the projectors to the two-particle eigenstates of the Hamiltonian. Then we compare this model with the data of the CPLEAR experiment and find in this way an upper bound on strength $\ensuremath{\lambda}$ of the decoherence. We also relate $\ensuremath{\lambda}$ to an effective decoherence parameter $\ensuremath{\zeta}$ considered previously in literature. Finally we discuss our model in the light of different measures of entanglement, i.e., von Neumann entropy S, entanglement of formation E, and concurrence C, and we relate decoherence parameter $\ensuremath{\zeta}$ to the loss of entanglement: $1\ensuremath{-}E.$

arXiv:quant-ph/0209017Physical Review AJul 30, 200379 citations

Quantum Entanglement

Paul Cummins

Jul 5, 20100 citations

XXY

models.