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arXiv · 1408.4396

Search for Millicharged Particles Using Optically Levitated Microspheres

David C. Moore·Alexander D. Rider·Giorgio Gratta
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Abstract

We report results from a search for stable particles with charge > $10^{-5}$ e in bulk matter using levitated dielectric microspheres in high vacuum. No evidence for such particles was found in a total sample of 1.4 ng, providing an upper limit on the abundance per nucleon of 2.5 x $10^{-14}$ at the 95% confidence level for the material tested. These results provide the first direct search for single particles with charge < 0.1 e bound in macroscopic quantities of matter and demonstrate the ability to perform sensitive force measurements using optically levitated microspheres in vacuum.

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hep-excond-mat.mes-hallphysics.ins-detphysics.optics

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David C. Moore, Alexander D. Rider, Giorgio Gratta. 2014-12-16. Search for Millicharged Particles Using Optically Levitated Microspheres. https://doi.org/10.1103/physrevlett.113.251801

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