Evolution of pairwise entanglement in a coupled nbody system
Abstract
We study the exact evolution of two noninteracting qubits, initially in a Bell state, in the presence of an environment, modeled by a kicked Ising spin chain. Dynamics of this model range from integrable to chaotic and we can handle numerics for a large number of qubits. We find that the entanglement (as measured by concurrence) of the two qubits has a close relation to the purity of the pair, and closely follows an analytic relation derived for Werner states. As a collateral result we find that an integrable environment causes quadratic decay of concurrence as well as of purity, while a chaotic environment causes linear decay. Both quantities display recurrences in an integrable environment.
 Authors:
 Instituto de Fisica, University of Mexico (UNAM) (Mexico)
 (UNAM) (Mexico)
 Centro de Ciencias Fisicas, University of Mexico (UNAM) (Mexico)
 (Mexico)
 Publication Date:
 OSTI Identifier:
 20786650
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.012305; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; BELL THEOREM; CHAOS THEORY; DECAY; EVOLUTION; IMPURITIES; INTEGRAL CALCULUS; ISING MODEL; QUANTUM COMPUTERS; QUANTUM ENTANGLEMENT; QUBITS; SPIN
Citation Formats
Pineda, Carlos, Centro de Ciencias Fisicas, University of Mexico, Seligman, Thomas H., and Centro Internacional de Ciencias, Cuernavaca. Evolution of pairwise entanglement in a coupled nbody system. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.0.
Pineda, Carlos, Centro de Ciencias Fisicas, University of Mexico, Seligman, Thomas H., & Centro Internacional de Ciencias, Cuernavaca. Evolution of pairwise entanglement in a coupled nbody system. United States. doi:10.1103/PHYSREVA.73.0.
Pineda, Carlos, Centro de Ciencias Fisicas, University of Mexico, Seligman, Thomas H., and Centro Internacional de Ciencias, Cuernavaca. Sun .
"Evolution of pairwise entanglement in a coupled nbody system". United States.
doi:10.1103/PHYSREVA.73.0.
@article{osti_20786650,
title = {Evolution of pairwise entanglement in a coupled nbody system},
author = {Pineda, Carlos and Centro de Ciencias Fisicas, University of Mexico and Seligman, Thomas H. and Centro Internacional de Ciencias, Cuernavaca},
abstractNote = {We study the exact evolution of two noninteracting qubits, initially in a Bell state, in the presence of an environment, modeled by a kicked Ising spin chain. Dynamics of this model range from integrable to chaotic and we can handle numerics for a large number of qubits. We find that the entanglement (as measured by concurrence) of the two qubits has a close relation to the purity of the pair, and closely follows an analytic relation derived for Werner states. As a collateral result we find that an integrable environment causes quadratic decay of concurrence as well as of purity, while a chaotic environment causes linear decay. Both quantities display recurrences in an integrable environment.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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