Local quantum uncertainty and interferometric power for a two-qubit system under decoherence channels with memory
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Via local quantum uncertainty (LQU) and interferometric power (IP) as a measure of nonclassical correlations, we study the dynamics of quantum correlations for two non-interacting qubits passing through decoherence channels where the channels with successive uses are correlated. The effect of three different types of decoherence channels, such as amplitude damping, phase damping, and depolarizing channels, on quantum correlations has been discussed in detail. The explicit analytical expressions of LQU and IP for a class of Bell-diagonal states under these decoherence channels have been derived. Our results show that the behaviors of both LQU and IP exhibit similar variation under the amplitude damping and phase damping channels, with monotonic decay from an increasing decoherence rate, but decay more slowly when the memory coefficient of the channel increases. Compared to the phenomenon of LQU under a depolarizing channel, we find that there exists a sudden change of LQU under both amplitude damping and phase damping channels by choosing proper initial parameters. Finally, we compare the dynamics of LQU with that of IP under decoherence channels. Our results also confirm the amount of quantum correlations measured by LQU is smaller than IP.
KeywordsLocal quantum uncertainty Interferometric power Quantum correlations Decoherence channels with memory
This work is supported by the National Natural Science Foundation of China under Grant No. 11747107, the Natural Science Foundation of Hunan Province (Grant No. 2017JJ3346), the Project of Science and Technology Plan of Changsha (K1705022 and kc1809023), the Scientific Research Project of Hunan Province Department of Education (Grant No. 18A373) and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education (QSQC1810).
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