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:1603.08555

Effect of quantum phase transition in the disentanglement of three spins coupled to an XY spin chain

Haifu Ma

Published Mar 25, 2016• 0 citations
arXivHTMLPDF

Abstract

Recently, along with the development of quantum information, quantum entanglemant became a hot topic of people. Quantum entanglemant is one of the most amazing phenomenon in quantum mechanics that is totally different from classical physics. However, system would interact with environment in the practical quantum information process. The entanglement would be broken. In this paper, we study the disentanglement evolution of three spin qubits in an XY spin-chain environment. The dynamical process of the disentanglement is investigated. We found the exact expression of the coherence factor. We discuss the coherence factor and the parameters, and then we illustrate that the disentanglement of central spins is best enhanced by the quantum critical behavior of the environmental spin chain. Furthermore, a scaling rule is obtained.

DOI
10.48550/arxiv.1603.08555

Related papers

Disentanglement of two qubits coupled to an XY spin chain: Role of quantum phase transition

Zi-Gang Yuan, Ping Zhang, Shu‐Shen Li

We study the disentanglement evolution of two spin qubits which interact with a general $XY$ spin-chain environment. The dynamical process of the disentanglement is numerically and analytically investigated in the vicinity of a quantum phase transition (QPT) of the spin chain in both weak and strong coupling cases. We find that the disentanglement of the two spin qubits may be greatly enhanced by the quantum critical behavior of the environmental spin chain. We give a detailed analysis to facilitate the understanding of the QPT-enhanced decaying behavior of the coherence factor. Furthermore, the scaling behavior in the disentanglement dynamics is also revealed and analyzed.

arXiv:0707.2846•Physical Review A•Oct 19, 2007•77 citations

Disentanglement of Two Qubits Coupled to an XY Spin Chain at Finite Temperature

Nie Jing, Lincheng Wang, Yi Xue-Xi

The disentanglement evolution of bipartite spin- 1 / 2 system coupled to a common surrounding XY chain in transverse fields at nonzero temperature is studied in this letter. The dynamical process of the entanglement is numerically and analytically investigated. We find that thermal effects can enhance disentanglement if the entangled initial state of the central spins does not in the decoherence free space. The critical phenomenon of quantum phase transitions reflected in the disentanglement can be washed out by the thermal effect eventually.

Communications in Theoretical Physics•May 1, 2009•6 citations

Dynamics of quantum coherence and correlations in a transverse Ising spin chain environment

Qi Han, Huan Wang, Shuai Wang +2 more

In this paper, we study the dynamical processes of quantum coherence and correlations for two central qubits system coupled with a transverse Ising spin chain. Suppose the initial state of quantum system is the Werner state and the initial state of environment is the ground state of spin chain, and the corresponding time evolution operator, decoherence factor and reduced density matrix are given. We deduce the analytical expressions of evolution of quantum coherence, entanglement and quantum discord. We find that when the spin chain undergoes quantum phase transition (QPT), the entanglement vanished at time [Formula: see text], and the coherence and discord vanished when the decoherence factor decayed to zero. Besides, we also find that the environmental scale N, coupling strength g and parameter P of Werner state do not change the evolution rules of quantum correlation, but accelerate their decay rate with these parameters’ increase.

International Journal of Modern Physics B•Jan 18, 2024•1 citation

Disentanglement in a quantum-critical environment

Zhe Sun, Xiaoguang Wang, C. P. Sun

We study the dynamical process of disentanglement of two qubits and two qutrits coupled to an Ising spin chain in a transverse field, which exhibits a quantum phase transition. We use the concurrence and negativity to quantify entanglement of two qubits and two qutrits, respectively. Explicit connections between the concurrence (negativity) and the decoherence factors are given for two initial states, the pure maximally entangled state and the mixed Werner state. We find that the concurrence and negativity decay exponentially with fourth power of time in the vicinity of the critical point of the environmental system.

arXiv:0704.1172•Physical Review A•Jun 11, 2007•130 citations

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

Ben‐Qiong Liu, Bin Shao, Jian Zou

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.

Physical Review A•Dec 10, 2009•16 citations

Quantum correlations dynamics of three-qubit states coupled to an XY spin chain: Role of coupling strengths

Shaoying Yin, Qingxin Liu, Jie Song +3 more

We investigate the prominent impacts of coupling strengths on the evolution of entanglement and quantum discord for a three-qubit system coupled to an XY spin-chain environment. In the case of a pure W state, more robust, even larger nonzero quantum correlations can be obtained by tailoring the coupling strengths between the qubits and the environment. For a mixed state consisting of the GHZ and W states, the dynamics of entanglement and quantum discord can characterize the critical point of quantum phase transition. Remarkably, a large nonzero quantum discord is generally retained, while the nonzero entanglement can only be obtained as the system-environment coupling satisfies certain conditions. We also find that the impact of each qubit’s coupling strength on the quantum correlation dynamics strongly depends on the variation schemes of the system-environment couplings.

Chinese Physics B•Sep 1, 2017•3 citations
Recently, along with the development of quantum information, quantum entanglemant became a hot topic of people. Quantum entanglemant is one of the most amazing phenomenon in quantum mechanics that is totally different from classical physics. However, system would interact with environment in the practical quantum information process. The entanglement would be broken. In this paper, we study the disentanglement evolution of three spin qubits in an XY spin-chain environment. The dynamical process of the disentanglement is investigated. We found the exact expression of the coherence factor. We discuss the coherence factor and the parameters, and then we illustrate that the disentanglement of central spins is best enhanced by the quantum critical behavior of the environmental spin chain. Furthermore, a scaling rule is obtained.
We study the disentanglement evolution of two spin qubits which interact with a general XYXYXY spin-chain environment. The dynamical process of the disentanglement is numerically and analytically investigated in the vicinity of a quantum phase transition (QPT) of the spin chain in both weak and strong coupling cases. We find that the disentanglement of the two spin qubits may be greatly enhanced by the quantum critical behavior of the environmental spin chain. We give a detailed analysis to facilitate the understanding of the QPT-enhanced decaying behavior of the coherence factor. Furthermore, the scaling behavior in the disentanglement dynamics is also revealed and analyzed.
The disentanglement evolution of bipartite spin- 1 / 2 system coupled to a common surrounding XY chain in transverse fields at nonzero temperature is studied in this letter. The dynamical process of the entanglement is numerically and analytically investigated. We find that thermal effects can enhance disentanglement if the entangled initial state of the central spins does not in the decoherence free space. The critical phenomenon of quantum phase transitions reflected in the disentanglement can be washed out by the thermal effect eventually.
In this paper, we study the dynamical processes of quantum coherence and correlations for two central qubits system coupled with a transverse Ising spin chain. Suppose the initial state of quantum system is the Werner state and the initial state of environment is the ground state of spin chain, and the corresponding time evolution operator, decoherence factor and reduced density matrix are given. We deduce the analytical expressions of evolution of quantum coherence, entanglement and quantum discord. We find that when the spin chain undergoes quantum phase transition (QPT), the entanglement vanished at time [Formula: see text], and the coherence and discord vanished when the decoherence factor decayed to zero. Besides, we also find that the environmental scale N, coupling strength g and parameter P of Werner state do not change the evolution rules of quantum correlation, but accelerate their decay rate with these parameters’ increase.
We study the dynamical process of disentanglement of two qubits and two qutrits coupled to an Ising spin chain in a transverse field, which exhibits a quantum phase transition. We use the concurrence and negativity to quantify entanglement of two qubits and two qutrits, respectively. Explicit connections between the concurrence (negativity) and the decoherence factors are given for two initial states, the pure maximally entangled state and the mixed Werner state. We find that the concurrence and negativity decay exponentially with fourth power of time in the vicinity of the critical point of the environmental system.
We investigate the entanglement dynamics of a two-qubit system which interacts with a Heisenberg XYXYXY 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.
We investigate the prominent impacts of coupling strengths on the evolution of entanglement and quantum discord for a three-qubit system coupled to an XY spin-chain environment. In the case of a pure W state, more robust, even larger nonzero quantum correlations can be obtained by tailoring the coupling strengths between the qubits and the environment. For a mixed state consisting of the GHZ and W states, the dynamics of entanglement and quantum discord can characterize the critical point of quantum phase transition. Remarkably, a large nonzero quantum discord is generally retained, while the nonzero entanglement can only be obtained as the system-environment coupling satisfies certain conditions. We also find that the impact of each qubit’s coupling strength on the quantum correlation dynamics strongly depends on the variation schemes of the system-environment couplings.