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arXiv · 2408.01177

Deterministic multipartite entanglement via fractional state transfer across quantum networks

G. F. Peñas·J. -J. García-Ripoll·R. Puebla
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Abstract

The generation of entanglement across different nodes in distributed quantum architectures plays a pivotal role for different applications. In particular, deterministic, robust, and fast protocols that prepare genuine multipartite entangled states are highly desirable. In this article, we propose a fractional quantum state transfer, in which the excitation of an emitter is partially transmitted through the quantum communication channel and then absorbed at a spatially separated node. This protocol is based on wavepacket shaping allowing for a fast deterministic generation of Bell states among two quantum registers and $W$ states for a general setting of $N$ qubits, either in a sequential or simultaneous fashion, depending on the topology of the network. By means of detailed numerical simulations, we show that genuine multipartite entangled states can be faithfully prepared within current experimental platforms and discuss the role of the main decoherence sources, qubit dephasing and relaxation, depending on the network topology.

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G. F. Peñas, J. -J. García-Ripoll, R. Puebla. 2024-10-17. Deterministic multipartite entanglement via fractional state transfer across quantum networks. https://arxiv.org/abs/2408.01177

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