Search for non-Newtonian interactions at micrometer scale with a levitated test mass

We report on a search for non-Newtonian forces that couple to mass, with characteristic scale of $\ensuremath{\sim}10\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$, using an optically levitated microsphere as precision force sensor. A silica trapped in upward-propagating, single-beam, optical tweezer is utilized probe interactions sourced from nanofabricated attractor mass density modulation brought into close proximity the and driven along axis periodic order excite oscillating response. obtain sensitivity $\ensuremath{\lesssim}{10}^{\ensuremath{-}16}\text{ }\mathrm{N}/\sqrt{\mathrm{Hz}}$. Separately searching attractive repulsive results constraint new Yukawa interaction $|\ensuremath{\alpha}|\ensuremath{\gtrsim}{10}^{8}$ $\ensuremath{\lambda}>10\text{ }\ensuremath{\mu}\mathrm{m}$. This first test inverse-square law dimensions comparable $\ensuremath{\lambda}$, complementary method subject different set systematic effects compared more established techniques.