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Entanglement of orbital angular momentum states between an ensemble of cold atoms and a photon

R. Inoue·N. Kanai·T. Yonehara·Y. Miyamoto·M. Koashi·M. Kozuma
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Abstract

Recently, atomic ensemble and single photons were successfully entangled by using collective enhancement [D. N. Matsukevich, \textit{et al.}, Phys. Rev. Lett. \textbf{95}, 040405(2005).], where atomic internal states and photonic polarization states were correlated in nonlocal manner. Here we experimentally clarified that in an ensemble of atoms and a photon system, there also exists an entanglement concerned with spatial degrees of freedom. Generation of higher-dimensional entanglement between remote atomic ensemble and an application to condensed matter physics are also discussed.

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R. Inoue, N. Kanai, T. Yonehara, Y. Miyamoto, M. Koashi, M. Kozuma. 2008-01-30. Entanglement of orbital angular momentum states between an ensemble of cold atoms and a photon. https://doi.org/10.1103/physreva.74.053809

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