Anomalous decay of quantum correlations of quantum dot qubits

Abstract

We study the evolution of quantum correlations, quantified by the geometric discord, of two excitonic quantum dot qubits under the influence of the phonon environment. We show that the decay of these correlations differs substantially form the decay of entanglement. Instead of displaying sudden death type behavior, the geometric discord shows a tendency to undergo transitions between different types of decay, is sensitive to non-local phase factors, and may already be enhanced by weak environment-mediated interactions. Hence, two-qubit quantum correlations are more robust under decoherence processes, while showing a richer and more complex spectrum of behavior under unitary and non-unitary evolution.

5 pages, 2 figures

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Cited by in corpus (7)

• Quantum discord and its allies: a review
• A scheme for direct detection of qubit-environment entanglement generated during qubit pure dephasing
• Equivalence of qubit-environment entanglement and discord generation via pure dephasing interactions and the consequences thereof
• Phonon-mediated generation of quantum correlations between quantum dot qubits
• Plasmon-assisted quantum control of distant emitters
• The relation between the quantum discord and quantum teleportation: the physical interpretation of the transition point between different quantum discord decay regimes
• The decay of quantum correlations between quantum dot spin qubits and the characteristics of its magnetic field dependence