Ultrasensitive Force Measurements with Optically Levitated Nanoparticles

The large mechanical quality factor of optically levitated dielectric particles makes them an ideal

tool for precision measurement experiments. Using these techniques, we have previously achieved

zepto-Newton force sensitivity. By improving our technology and experimental methods, we report

progress on improved studies of the Newtonian gravitational inverse square law at micron length

scales. These measurements will place stronger limits on possible Yukawa type corrections to Newtonian

gravity in the sub millimeter regime.