# Entanglement with negative Wigner function of almost 3,000 atoms heralded by one photon

@article{McConnell2015EntanglementWN, title={Entanglement with negative Wigner function of almost 3,000 atoms heralded by one photon}, author={Robert McConnell and Hao Zhang and Jiazhong Hu and Senka {\'C}uk and Vladan Vuleti{\'c}}, journal={Nature}, year={2015}, volume={519}, pages={439-442} }

Quantum-mechanically correlated (entangled) states of many particles are of interest in quantum information, quantum computing and quantum metrology. Metrologically useful entangled states of large atomic ensembles have been experimentally realized, but these states display Gaussian spin distribution functions with a non-negative Wigner quasiprobability distribution function. Non-Gaussian entangled states have been produced in small ensembles of ions, and very recently in large atomic ensembles…

## 170 Citations

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