Precision scanning force sensing with nanoparticles in optical lattices

In high vacuum, optically levitated dielectric nanospheres achieve excellent decoupling from their environment, making them ultra-sensitive detectors of feeble forces and accelerations. In this talk I will describe our results on three-dimensional scanning force sensing using optically trapped nanoparticles trapped in an optical lattice at micron-scale distances from a metallic mirror and discuss our progress towards applying these techniques for tests of the gravitational inverse square law at micron scales. Finally, I will describe our progress towards using non-spherical nanoparticles trapped in optical lattices to search for high-frequency gravitational waves.