共查询到10条相似文献,搜索用时 93 毫秒
1.
2.
Correlation dynamics of a qubit–qutrit system in a spin-chain environment with Dzyaloshinsky–Moriya interaction 下载免费PDF全文
We study the dynamics of correlations for a hybrid qubit-qutrit system in an XY spin-chain environment with Dzyaloshinsky-Moriya interaction. Our discussion involves a comparative analysis of negativity, quantum discord, and measurement-induced disturbance. It is found that the quantum discord is optimal of the three quantum correlations to de- tect the critical point of quantum phase transition. Only when the qubit interacts with the environment, is the phenomenon of sudden transition between the classical correlation and the quantum discord observed. Moreover, the Dzyaloshinsky- Moriya interaction enhances the decay of quantum correlations. 相似文献
3.
4.
We investigate the necessary conditions for the existence of sudden transition or sudden change phenomenon for appropriate initial states under dephasing. As illustrative examples, we study the behaviors of quantum correlation dynamics of two noninteracting qubits in independent and common open spin environments, respectively. For the independent environments case, we find that the quantum correlation dynamics is closely related to the Loschmidt echo and the dynamics exhibits a sudden transition from classical to quantum correlation decay. It is also shown that the sudden change phenomenon may occur for the common environment case and stationary quantum discord is found at the high temperature region of the environment. Finally, we investigate the quantum criticality of the open spin environment by exploring the probability distribution of the Loschmidt echo and the scaling transformation behavior of quantum discord, respectively. 相似文献
5.
We study the time evolution of classical and quantum correlations for hybrid qubit-qutrit systems in independent and common dephasing environments. Our discussion involves a comparative analysis of the Markovian dynamics of negativity, quantum discord, geometric measure of quantum discord and classical correlation. For the case of independent environments, we have demonstrated the phenomenon of sudden transition between classical and quantum decoherence for qubit-qutrit states. In the common environment case, we have shown that dynamics of quantum and geometric discords might be completely independent of each other for a certain time interval, although they tend to be eventually in accord. 相似文献
6.
Ying-Juan Mi 《International Journal of Theoretical Physics》2012,51(2):544-553
We study the dynamics of classical correlation and quantum discord of two-qubit system interacted with the thermal reservoir.
Special attention is paid to the difference between the entanglement and quantum discord when considering the influences of
the nonzero mean photon number and quantum fluctuation of the vacuum. It is shown that in the same range of the physical parameters,
the factors leading to the entanglement sudden death only accelerates the decay of quantum discord, and the quantum discord
can last for an infinite period when the entanglement disappears. So the quantum discord is more robust than entanglement
under this decoherence environment, and quantum discord is a more general measure of quantum correlation than entanglement. 相似文献
7.
The dynamics of quantum discord for two qubits independently interacting with dephasing reservoirs have been studied recently.The authors [Phys.Rev.A 88(2013) 034304] found that for some Bell-diagonal states(BDS)which interact with their environments the calculation of quantum discord could experience a sudden transition in its dynamics,this phenomenon is known as the sudden change.Here in the present paper,we analyze the dynamics of normal quantum discord and super quantum discord for tripartite Bell-diagonal states independently interacting with dephasing reservoirs.Then,we find that basis change does not necessary mean sudden change of quantum correlations. 相似文献
8.
Control of sudden transition between classical and quantum correlations of two strongly driven atoms in dissipative cavities 下载免费PDF全文
We investigate analytically the dynamics of classical and quantum correlations between two strongly driven atoms, each of which is trapped inside a dissipative cavity. It is found that there exists a finite time interval during which the quantum discord initially prepared in the X-type states is not destroyed by the decay of the cavities. The sudden transition between classical correlation and quantum discord is sensitive to the initial-state parameter, the cavity decay rate, and the cavity mode-driving field detuning. Interestingly, we show that the transition time can be prolonged significantly by increasing the degree of the detuning. 相似文献
9.
The quantum entanglement,discord,and coherence dynamics of two spins in the model of a spin coupled to a spin bath through an intermediate spin are studied.The effects of the important physical parameters including the coupling strength of two spins,the interaction strength between the intermediate spin and the spin bath,the number of bath spins and the temperature of the system on quantum coherence and correlation dynamics are discussed in different cases.The frozen quantum discord can be observed whereas coherence does not when the initial state is the Bell-diagonal state.At finite temperature,we find that coherence is more robust than quantum discord,which is better than entanglement,in terms of resisting the influence of environment.Therefore,quantum coherence is more tenacious than quantum correlation as an important resource. 相似文献
10.
Xiang-Ping Liao Jian-Shu Fang Mao-Fa Fang Zhong Huang 《International Journal of Theoretical Physics》2011,50(9):2631-2643
We study the dynamics of quantum discord between two qubits coupled collectively to a thermal reservoir. For comparison, we
also consider the dynamics of quantum entanglement. It is shown that we can obtain a stable quantum discord induced by the
thermal environment when the discord of the initial state is zero. The thermal environment can also induce a stable amplification
of the initially prepared quantum discord for certain X-type states. It is very valuable that the quantum discord is more
resistant against the thermal environment than quantum entanglement. And, we have demonstrated that the sudden death of discord
in a Markovian regime is impossible even at high temperature. It provides us a feasible way to create and protect quantum
correlation in the case of a high-temperature thermal environment for various physical system such as trapped ions, quantum
dots or Josephson junctions. 相似文献