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arXiv · 2102.13082

Continuous variable multipartite vibrational entanglement

Mehdi Abdi
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Abstract

A compact scheme for the preparation of macroscopic multipartite entanglement is proposed and analyzed. In this scheme the vibrational modes of a mechanical resonator constitute continuous variable (CV) subsystems that entangle to each other as a result of their interaction with a two-level system (TLS). By properly driving the TLS, we show that a selected set of modes can be activated and prepared in a multipartite entangled state. We first study entanglement properties of a three-mode system by evaluating the genuine multipartite entanglement. And investigate its usefulness as a quantum resource by computing the quantum Fisher information. Moreover, the robustness of the state against the qubit and thermal noises is studied, proving a long-lived entanglement. To examine the scalability and structural properties of the scheme, we derive an effective model for the multimode system through elimination of the TLS dynamics. This work provides a step towards a compact and versatile device for creating multipartite noise-resilient entangled state in vibrational modes as a resource for CV quantum metrology, quantum communication, and quantum computation.

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Mehdi Abdi. 2021-05-16. Continuous variable multipartite vibrational entanglement. https://doi.org/10.1103/physreva.103.043520

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