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Search for exchange-antisymmetric two-photon states

D. DeMille·D. Budker·N. Derr·E. Deveney
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Abstract

Atomic two-photon J=0 $\leftrightarrow$J'=1 transitions are forbidden for photons of the same energy. This selection rule is related to the fact that photons obey Bose-Einstein statistics. We have searched for small violations of this selection rule by studying transitions in atomic Ba. We set a limit on the probability $v$ that photons are in exchange-antisymmetric states: $v<1.2\cdot10^{-7}$.

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D. DeMille, D. Budker, N. Derr, E. Deveney. 1999-09-25. Search for exchange-antisymmetric two-photon states. https://doi.org/10.1103/physrevlett.83.3978

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