Non-Markovian decoherence dynamics of entangled coherent states
Jun-Hong An, Mang Feng, Wei-Min Zhang
备注:
10 pages, 3 figures. The Markovian limit of the derived non-Markovian master equation is added. Also the numerical results of comparing the non-Markovian with Markovian decoherence dynamics of the entangled coherent states are added
We microscopically model the decoherence dynamics of entangled coherent states under the influence of vacuum fluctuation. We derive an exact master equation with time-dependent coefficients reflecting the memory effect of the environment, by using the Feynman-Vernon influence functional theory in the coherent-state representation. Under the Markovian approximation, our master equation recovers the widely used Lindblad equation in quantum optics. We then investigate the non-Markovian entanglement dynamics of the quantum channel in terms of the entangled coherent states under noise. Compared with the results in Markovian limit, it shows that the non-Markovian effect enhances the disentanglement to the initially entangled coherent state. Our analysis also shows that the decoherence behaviors of the entangled coherent states depend sensitively on the symmetrical properties of the entangled coherent states as well as the interactions between the system and the environment.
Steady-State Coherences under Partial Collective non-Markovian Decoherence
Dalian Minzu University(大连民族大学);Ocean University of China(中国海洋大学);University of Toronto(多伦多大学);University of the Basque Country UPV/EHU(巴斯克大学);IKERBASQUE, Basque Foundation for Science(伊卡巴斯基克科学基金会)
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Chirality asymptotic behavior and non-Markovianity in quantum walks on a line
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Poornaprajna Institute of Scientific Research (PPISR)(普尔纳普拉吉纳科学研究学院);Manipal Academy of Higher Education(马帕尔高等教育学院);Amrita Vishwa Vidyapeetham(阿弥塔大学);National Institute for Theoretical and Computational Sciences (NITheCS)(理论与计算科学国家研究所);Chennai Institute of Technology(金奈理工学院)