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arXiv · 1311.5953

Finite-temperature decoherence of spin states in a $\texttt{\{}\emph{Cu}_3\texttt{\}}$ single molecular magnet

Xiang Hao·Xiaoqun Wang·Chen Liu·Shiqun Zhu
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Abstract

We investigate the quantum evolution of spin states of a single molecular magnet in a local electric field. The decoherence of a $\texttt{\{}\emph{Cu}_3\texttt{\}}$ single molecular magnet weakly coupled to a thermal bosonic environment can be analyzed by the spin-boson model. Using the finite-temperature time-convolutionless quantum master equation, we obtain the analytical expression of the reduced density matrix of the system in the secular approximation. The suppressed and revived dynamical behavior of the spin states are presented by the oscillation of the chirality spin polarization on the time scale of the correlation time of the environment. The quantum decoherence can be effectively restrained with the help of the manipulation of local electric field and the environment spectral density function. Under the influence of the dissipation, the pointer states measured by the von Neumann entropy are calculated to manifest the entanglement property of the system-environment model.

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Xiang Hao, Xiaoqun Wang, Chen Liu, Shiqun Zhu. 2013-11-23. Finite-temperature decoherence of spin states in a $\texttt{\{}\emph{Cu}_3\texttt{\}}$ single molecular magnet. https://doi.org/10.1088/0953-4075%2F46%2F2%2F025502

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