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arXiv · 1308.6174

Generating Entangled Spin States for Quantum Metrology by Single-Photon Detection

Robert McConnell·Hao Zhang·Senka Ćuk·Jiazhong Hu·Monika H. Schleier-Smith·Vladan Vuletić
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Abstract

We propose and analyze a probabilistic but heralded scheme to generate pure, entangled, non-Gaussian states of collective spin in large atomic ensembles by means of single-photon detection. One photon announces the preparation of a Dicke state, while two or more photons announce Schrödinger cat states. The method produces pure states even for finite photon detection efficiency and weak atom-photon coupling. The entanglement generation can be made quasi-deterministic by means of repeated trial and feedback, enabling metrology beyond the standard quantum limit.

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Robert McConnell, Hao Zhang, Senka Ćuk, Jiazhong Hu, Monika H. Schleier-Smith, Vladan Vuletić. 2013-08-28. Generating Entangled Spin States for Quantum Metrology by Single-Photon Detection. https://doi.org/10.1103/physreva.88.063802

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