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Sub-micron force detection using optically-cooled levitated microspheres



Andrew Geraci, Scott B. Papp, John E. Kitching


We propose an experiment using optically trapped and cooled dielectric microspheres for the detection of short-range forces. The center-of-mass motion of a microsphere trapped in vacuum can experience extremely low dissipation and quality factors of 1012, leading to yoctoNewton force sensitivity. Trapping the sphere in an optical field enables positioning at less than 1 υm from a surface, a regime where exotic new forces may exist. We expect that the proposed system could advance the search for non-Newtonian gravity forces via an enhanced sensitivity of 105 -107 over current experiments at the micron length scale. Moreover, our system may be useful for characterizing other short-range physics such as Casimir forces.
Physical Review


Casimir force, cavity cooling, non-Newtonian gravity, optical trapping, optomechanics


Geraci, A. , Papp, S. and Kitching, J. (2010), Sub-micron force detection using optically-cooled levitated microspheres, Physical Review, [online], (Accessed May 24, 2024)


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Created September 3, 2010, Updated February 19, 2017