Evolution from entanglement to decoherence

We examine a class of bipartite mixed states which we call X states and report several analytic results related to the occurrence of early-stage decoherence or so-called entanglement sudden death (ESD) under time evolution in the presence of common types of environmental noise. Avoidance of sudden death by application of purely local operations is shown to be feasible in some cases.

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A NEW FEATURE ON THE SUDDEN DEATH OF ENTANGLEMENT

Modern Physics Letters B ◽

10.1142/s021798490801687x ◽

2008 ◽

Vol 22 (25) ◽

pp. 2503-2508 ◽

Cited By ~ 1

Author(s):

XUE-QUN YAN

Keyword(s):

Sudden Death ◽

Time Evolution ◽

Analytic Solution ◽

Time Interval ◽

Entanglement Sudden Death ◽

Mixed States ◽

Initial States ◽

New Feature

Based on the exactly analytic solution obtained of the intensity-dependent Jaynes–Cummings model for a certain class of initial entangled mixed states, we explore the time evolution of the entanglement between two atoms, initially non-locally correlated and separately interacting with two distinct cavities. The results show that entanglement sudden death is dependent on the different initial states of atoms, and the length of the time interval for the zero entanglement is invariant for a certain class of initial mixed states.

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DYNAMICAL SUPPRESSION OF ENTANGLEMENT SUDDEN DEATH IN A JAYNES–CUMMINGS MODEL EXTENDED

Modern Physics Letters B ◽

10.1142/s0217984909017911 ◽

2009 ◽

Vol 23 (02) ◽

pp. 163-169

Author(s):

XUE-QUN YAN

Keyword(s):

Sudden Death ◽

Time Evolution ◽

Electromagnetic Pulse ◽

Atomic Motion ◽

Single Atom ◽

Entanglement Sudden Death ◽

Mode Structure ◽

Elementary Model ◽

Finite Duration

The Jaynes–Cummings model extended by the inclusion of mode structure and atomic motion is an elementary model that describes the interaction between a single atom and electromagnetic pulse. Based on the model, we explore the time evolution of the entanglement between two atoms, initially non-locally correlated and crossing separately two distinct cavities. Our results show that this model suggests a strategy to fight against the so-called entanglement sudden death, and in the situation resurrection of the original entanglement value occurs periodically and the entanglement will remain at the original value for a finite duration.

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Entanglement Sudden Death and Birth Effects in Two Qubits Maximally Entangled Mixed States Under Quantum Channels

International Journal of Theoretical Physics ◽

10.1007/s10773-019-04332-z ◽

2019 ◽

Vol 59 (2) ◽

pp. 403-414 ◽

Cited By ~ 2

Author(s):

Kapil K. Sharma ◽

Vladimir P. Gerdt

Keyword(s):

Sudden Death ◽

Entanglement Sudden Death ◽

Quantum Channels ◽

Mixed States

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Effects of quantum error correction on entanglement sudden death

Quantum Information and Computation ◽

10.26421/qic14.1-2-3 ◽

2014 ◽

Vol 14 (1&2) ◽

pp. 39-55

Author(s):

Muhammed Yonac ◽

Joseph H. Eberly

Keyword(s):

Sudden Death ◽

Error Correction ◽

Quantum Coherence ◽

Early Stage ◽

Entanglement Sudden Death ◽

Mixing Angle ◽

Phase Damping ◽

Pure Phase ◽

Non Local ◽

Quantum Error

We investigate the effects of error correction on non-local quantum coherence as a function of time, extending the study by Sainz and Bjork. We consider error correction of amplitude damping, pure phase damping and combinations of amplitude and phase damping as they affect both fidelity and quantum entanglement. Initial two-qubit entanglement is encoded in arbitrary real superpositions of both $\Phi$-type and $\Psi$-type Bell states. Our main focus is on the possibility of delay or prevention of ESD (early stage decoherence, or entanglement sudden death). We obtain the onset times for ESD as a function of the state-superposition mixing angle. Error correction affects entanglement and fidelity differently, and we exhibit initial entangled states for which error correction increases fidelity but decreases entanglement, and vice versa.

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