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arXiv · 2306.13573

A photonic which-path entangler based on longitudinal cavity-qubit coupling

Z. M. McIntyre·W. A. Coish
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Abstract

We show that a modulated longitudinal cavity-qubit coupling can be used to control the path taken by a multiphoton coherent-state wavepacket conditioned on the state of a qubit, resulting in a qubit-which-path (QWP) entangled state. QWP states can generate long-range multipartite entanglement using strategies for interfacing discrete- and continuous-variable degrees-of-freedom. Using the approach presented here, entanglement can be distributed in a quantum network without the need for single-photon sources or detectors.

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Z. M. McIntyre, W. A. Coish. 2023-06-23. A photonic which-path entangler based on longitudinal cavity-qubit coupling. https://doi.org/10.1103/physrevlett.132.093603

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