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arXiv · 1511.08434

Phonon-mediated generation of quantum correlations between quantum dot qubits

Jan Krzywda·Katarzyna Roszak
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Abstract

We study the generation of quantum correlations between two excitonic quantum dot qubits due to their interaction with the same phonon environment. Such generation results from the fact that during the pure dephasing process at finite temperatures, each exciton becomes entangled with the phonon environment. We find that for a wide range of temperatures quantum correlations are created due to the interaction. The temperature-dependence of the amount of correlations created displays a trade-off type behaviour; for small temperatures the phonon-induced distrubance of the qubit states is too small to lead to a distinct change of the two-qubit state, hence, the amount of created correlations is small, while for large temperatures the pure dephasing is not accompanied by the creation of entanglement between the qubits and the environment, so the environment cannot mediate qubit-qubit quantum correlations.

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Jan Krzywda, Katarzyna Roszak. 2016-04-05. Phonon-mediated generation of quantum correlations between quantum dot qubits. https://doi.org/10.1038/srep23753

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