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arXiv · 2402.05080

Designing three-way entangled and nonlocal two-way entangled single particle states via alternate quantum walks

Dinesh Kumar Panda·Colin Benjamin
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Abstract

Entanglement with single-particle states is advantageous in quantum technology because of their ability to encode and process information more securely than their multi-particle analogs. Threeway and nonlocal two-way entangled single-particle states are desirable in this context. Herein, we generate genuine three-way entanglement from an initially separable state involving three degrees of freedom of a quantum particle, which evolves via a 2D alternate quantum walk employing a resource-saving single-qubit coin. We achieve maximum possible values for the three-way entanglement quantified by the {\pi}-tangle between the three degrees of freedom. We also generate optimal nonlocal two-way entanglement, quantified by the negativity between the nonlocal position degrees of freedom of the particle. This prepared architecture using quantum walks can be experimentally realized with a photon.

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Dinesh Kumar Panda, Colin Benjamin. 2024-02-07. Designing three-way entangled and nonlocal two-way entangled single particle states via alternate quantum walks. https://doi.org/10.1103/physreva.111.012420

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