Short-range force detection using optically-cooled levitated microspheres

TL;DR

This paper proposes using optically cooled levitated microspheres to detect extremely weak short-range forces, potentially surpassing current experimental sensitivities and enabling new physics discoveries at microscopic scales.

Contribution

It introduces a novel experimental setup with optically trapped and cooled microspheres for high-sensitivity short-range force detection, including non-Newtonian gravity and Casimir forces.

Findings

Potential to improve sensitivity by 10^5-10^7 times over current methods

Capable of detecting forces at less than 1 μm from surfaces

Suitable for exploring exotic new physics phenomena

Abstract

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 $10^{12}$, leading to yoctonewton force sensitivity. Trapping the sphere in an optical field enables positioning at less than 1 $\mu$m 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 $10^5-10^7$ over current experiments at the 1 $\mu$m length scale. Moreover, our system may be useful for characterizing other short-range physics such as Casimir forces.