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Non-zero quantum discord at finite temperature

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Abstract

We investigate theoretically the quantum discord dynamics of a two-qubit composite system subject to a common finite- temperature reservoir by solving the Born-Markovian master equation analytically. The ultimate quantum discord, however, exhibits a relatively high stable value associated with the reservoir temperature despite the permanent disappearance of entanglement simultaneously. Further analysis shows that the unique characteristic depends strongly on the off-diagonal non-zero elements of the density matrix. Our result manifests the greater robustness of quantum discord compared with entanglement, which may be helpful in quantum-information technologies.

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Authors and Affiliations

  1. State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-Sen University, Guangzhou, 510275, China

    XiangYang Yu, JianHong Li & XiaoBin Li

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  1. XiangYang Yu
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  2. JianHong Li
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  3. XiaoBin Li
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Correspondence to XiangYang Yu.

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Yu, X., Li, J. & Li, X. Non-zero quantum discord at finite temperature. Sci. China Phys. Mech. Astron. 55, 815–821 (2012). https://doi.org/10.1007/s11433-012-4710-0

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  • DOI: https://doi.org/10.1007/s11433-012-4710-0

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