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arXiv · 2106.00224

Witnessing entanglement via the geometric phase in a impurity-doped Bose-Einstein condensate

X. Wu·S. P. Jia·C. L. Cai·L. M. Kuang
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Abstract

We propose a theoretical scheme to witness quantum entanglement via the geometric phase in an impurity-doped Bose-Einstein condensate (BEC), which is a micro-macro quantum system consisting of two Rydberg impurity qubits and the BEC. We calculate the geometric phase of the impurity qubits in the presence of the initial micro-micro and micro-macro entanglement, respectively. It is demonstrated that the geometric phase of the impurity qubits can witness not only inter-qubit micro-micro entanglement, but also qubit-BEC micro-macro entanglement. Our work provide a new insight to witness micro-micro and micro-macro entanglement in a impurity-doped BEC.

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X. Wu, S. P. Jia, C. L. Cai, L. M. Kuang. 2021-06-01. Witnessing entanglement via the geometric phase in a impurity-doped Bose-Einstein condensate. https://arxiv.org/abs/2106.00224

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