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arXiv · 2212.11961

Engineering Graph States of Atomic Ensembles by Photon-Mediated Entanglement

Eric S. Cooper·Philipp Kunkel·Avikar Periwal·Monika Schleier-Smith
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Abstract

Graph states are versatile resources for quantum computation and quantum-enhanced measurement. Their generation illustrates a high level of control over entanglement. We report on the generation of continuous-variable graph states of atomic spin ensembles, which form the nodes of the graph. The edges represent the entanglement structure, which we program by combining global photon-mediated interactions in an optical cavity with local spin rotations. By tuning the entanglement between two subsystems, we either localize correlations within each subsystem or enable Einstein-Podolsky-Rosen steering. We further engineer a four-mode square graph state, highlighting the flexibility of our approach. Our method is scalable to larger and more complex graphs, laying groundwork for measurement-based quantum computation and advanced protocols in quantum metrology.

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Eric S. Cooper, Philipp Kunkel, Avikar Periwal, Monika Schleier-Smith. 2022-12-22. Engineering Graph States of Atomic Ensembles by Photon-Mediated Entanglement. https://doi.org/10.1038/s41567-024-02407-1

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