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Title: Entanglement of two qubits coupled to an XY spin chain: Role of energy current

Abstract

We investigate the entanglement dynamics of a two-qubit system which interacts with a Heisenberg XY spin chain constrained to carry an energy current. We show an explicit connection between the decoherence factor and entanglement, and numerically and analytically study the dynamical process of entanglement in both weak- and strong-coupling cases for two initial states, the general pure state and the mixed Werner state. We provide results that the entanglement evolution depends not only on the energy current, the anisotropy parameter and the system-environment couplings but also on the size of degrees of freedom of environment. In particular, our results imply that entanglement will be strongly suppressed by the introduction of energy current on the environmental spin chain in the weak-coupling region while it is not sensitive to the energy current in the strong-coupling region. We also observe the sudden death of entanglement in the system and show how the energy current affects the phenomenon.

Authors:
; ;  [1]
  1. Department of Physics, Beijing Institute of Technology, Beijing 100081 (China)
Publication Date:
OSTI Identifier:
21352322
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 80; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.80.062322; (c) 2009 The American Physical Society
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; COUPLING; CURRENTS; DEGREES OF FREEDOM; HEISENBERG MODEL; NUMERICAL ANALYSIS; QUANTUM COMPUTERS; QUANTUM ENTANGLEMENT; QUBITS; SPIN; STRONG-COUPLING MODEL; ANGULAR MOMENTUM; COMPUTERS; CRYSTAL MODELS; INFORMATION; MATHEMATICAL MODELS; MATHEMATICS; PARTICLE MODELS; PARTICLE PROPERTIES; QUANTUM INFORMATION

Citation Formats

Liu Benqiong, Shao Bin, and Zou Jian. Entanglement of two qubits coupled to an XY spin chain: Role of energy current. United States: N. p., 2009. Web. doi:10.1103/PHYSREVA.80.062322.
Liu Benqiong, Shao Bin, & Zou Jian. Entanglement of two qubits coupled to an XY spin chain: Role of energy current. United States. doi:10.1103/PHYSREVA.80.062322.
Liu Benqiong, Shao Bin, and Zou Jian. 2009. "Entanglement of two qubits coupled to an XY spin chain: Role of energy current". United States. doi:10.1103/PHYSREVA.80.062322.
@article{osti_21352322,
title = {Entanglement of two qubits coupled to an XY spin chain: Role of energy current},
author = {Liu Benqiong and Shao Bin and Zou Jian},
abstractNote = {We investigate the entanglement dynamics of a two-qubit system which interacts with a Heisenberg XY spin chain constrained to carry an energy current. We show an explicit connection between the decoherence factor and entanglement, and numerically and analytically study the dynamical process of entanglement in both weak- and strong-coupling cases for two initial states, the general pure state and the mixed Werner state. We provide results that the entanglement evolution depends not only on the energy current, the anisotropy parameter and the system-environment couplings but also on the size of degrees of freedom of environment. In particular, our results imply that entanglement will be strongly suppressed by the introduction of energy current on the environmental spin chain in the weak-coupling region while it is not sensitive to the energy current in the strong-coupling region. We also observe the sudden death of entanglement in the system and show how the energy current affects the phenomenon.},
doi = {10.1103/PHYSREVA.80.062322},
journal = {Physical Review. A},
number = 6,
volume = 80,
place = {United States},
year = 2009,
month =
}
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