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Experimental Observation of Magic-Wavelength Behavior in Optical Lattice-Trapped 87 Rb



James V. Porto, Nathan Lundblad, Malte Schlosser


We demonstrate the cancellation of the differential ac Stark shift of the microwave hyperfine clock transition in trapped 87 Rb atoms. Recent progress in metrology exploits so-called “magic wavelengths,” whereby an atomic ensemble can be trapped with laser light whose wavelength is chosen such that both levels of an optical atomic transition experience identical ac Stark shifts. Similar magic-wavelength techniques are not possible for the microwave hyperfine transitions in the alkalis, due to their simple electronic structure. We show, however, that ac Stark shift cancellation is indeed achievable for certain values of wavelength, polarization, and magnetic field. The cancelation comes at the expense of a small magnetic-field sensitivity. The technique demonstrated here has implications for experiments involving the precise control of optically-trapped neutral atoms.
Physical Review Letters


clock transitions, cold atoms, light shift, optical lattice


Porto, J. , Lundblad, N. and Schlosser, M. (2010), Experimental Observation of Magic-Wavelength Behavior in Optical Lattice-Trapped 87 Rb, Physical Review Letters (Accessed April 18, 2024)
Created March 29, 2010, Updated April 17, 2018