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Published on: November 11, 2013
Long-range molecular resonances in a cold Rydberg gas
S M Farooqi1, D Tong, S Krishnan
1Department of Physics, U-3046, University of Connecticut, Storrs, CT 06269, USA.
Abstract:
We present evidence for molecular resonances in a cold dense gas of rubidium Rydberg atoms. Single UV photon excitation from the 5s ground state to np Rydberg states (n=50-90) reveals resonances at energies corresponding to excited atom pairs (n-1)d+ns. We attribute these normally forbidden transitions to avoided crossings between the long-range molecular potentials of two Rydberg atoms. These strong van der Waals interactions result in avoided crossings at extremely long range, e.g., approximately 58 000 times the Bohr radius (a(0)) for n=70.
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