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Cold Collision Frequency Shift in Two-Dimensional Atomic Hydrogen

J. Ahokas·J. Jarvinen·S. Vasiliev
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Abstract

We report a measurement of the cold collision frequency shift in atomic hydrogen gas adsorbed on the surface of superfluid 4He at T<=90 mK. Using two-photon electron and nuclear magnetic resonance in 4.6 T field we separate the resonance line shifts due to the dipolar and exchange interactions, both proportional to surface density sigma. We find the clock shift Delta v_c = -1.0(1)x10^-7 Hz cm^-2 x sigma, which is about 100 times smaller than the value predicted by the mean field theory and known scattering lengths in the 3D case.

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J. Ahokas, J. Jarvinen, S. Vasiliev. 2006-10-27. Cold Collision Frequency Shift in Two-Dimensional Atomic Hydrogen. https://doi.org/10.1103/physrevlett.98.043004

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