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Coulomb bound states of strongly interacting photons



Mohammad F. Maghrebi, Michael Gullans, Przemek Bienias, Soonwon Choi, Ivar Martin, Ofer Firstenberg, Mikhail D. Lukin, Hans Peter Buchler, Alexey Gorshkov


We show that two photons coupled to Rydberg states via electromagnetically induced transparency can interact via an effective Coulomb potential. This interaction gives rise to a continuum of two-body bound states. Within the continuum, metastable bound states are distinguished in analogy with quasibound states tunneling through a potential barrier. We find multiple branches of metastable bound states whose energy spectrum is governed by the Coulomb potential, thus obtaining a photonic analogue of the hydrogen atom. Under certain conditions, the wave function resembles that of a diatomic molecule in which the two polaritons are separated by a finite "bond length." These states propagate with a negative group velocity in the medium, allowing for a simple preparation and detection scheme, before they slowly decay to pairs of bound Rydberg atoms.
Physical Review Letters


quantum optics, Rydberg atoms, interacting photons


Maghrebi, M. , Gullans, M. , Bienias, P. , Choi, S. , Martin, I. , Firstenberg, O. , Lukin, M. , Buchler, H. and Gorshkov, A. (2015), Coulomb bound states of strongly interacting photons, Physical Review Letters, [online],, (Accessed June 22, 2024)


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Created September 17, 2015, Updated October 12, 2021