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Measurement of the Casimir-Polder Force Through Center of Mass Oscillations of a Bose Einstein Condensate



D M. Harber, J Obrecht, J M. McGuirk, Eric A. Cornell


We have performed a measurement of the Casimir Polder force using a magnetically trapped ^u87Rb Bose Einstein condensate. By detecting perturbations of the frequency of center of mass oscillation of the condensate perpendicular to the surface, we are able to detect this force at a distance proportional to 5 m, significantly further than has been previously achieved, and at a precision approaching that needed to detect the modification due to thermal radiation. Additionally, this technique provides a limit for the precense of exotic forces in the proportional to 1 m range.
Physical Review A (Atomic, Molecular and Optical Physics)


atom surface interactions, Bose Einstein condensates
Created September 1, 2005, Updated February 17, 2017