Modifying friction by manipulating normal response to lateral motion

We investigate the coupled lateral-normal response to a lateral external dr ive in a nanoscale molecular system confined between two atomically smooth solid surfaces. We discuss the effects of shear induced dilatancy, which re sults from the coupling, on the energy dissipation, and therefore on the fr ictional properties. It is demonstrated that measurements of response in th e normal direction provide additional information on the mechanisms of fric tion and that manipulating the dilatancy opens new possibilities to control the motion in the lateral direction. The dilatancy leads to a novel memory effect which is amenable to experimental verification.