New constraints on ultrashort-ranged Yukawa interactions from atomic force microscopy

Many extensions to the standard model lead to the possibility of new forces which would produce Yukawa corrections to Newtonian gravity. Models in which the gravitational and gauge interactions are unified at ~1TeV using large extra dimensions could produce Yukawa-type corrections to the Newtonian gravitational law at submillimeter distances. In some models with $n=3$ extra dimensions, deviations from Newtonian gravity would occur at separations ~5nm, a distance scale accessible to an atomic force microscope (AFM). Here we present constraints on the Yukawa corrections derived from the latest AFM Casimir force measurement by Mohideen et al. which are up to 19 times stronger than those obtained from their previous experiment. We then discuss new designs for AFM experiments which have the potential to significantly improve upon these constraints.