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Entanglement dynamics of two nitrogen vacancy centers coupled by a nanomechanical resonator

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 Publication date 2017
  fields Physics
and research's language is English




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In this paper we study the time evolution of the entanglement between two remote NV Centers (nitrogen vacancy in diamond) connected by a dual-mode nanomechanical resonator with magnetic tips on both sides. Calculating the negativity as a measure for the entanglement, we find that the entanglement between two spins oscillates with time and can be manipulated by varying the parameters of the system. We observed the phe- nomenon of a sudden death and the periodic revivals of entanglement in time. For the study of quantum deco- herence, we implement a Lindblad master equation. In spite of its complexity, the model is analytically solvable under fairly reasonable assumptions, and shows that the decoherence influences the entanglement, the sudden death, and the revivals in time.



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