Adventures at high fields: from surface-charge inversion to nanopore ion-transport and molecular rotation

Whenever two surfaces are at nanometer separation, as when they are in or close to contact, even small potential differences (<0.5V) between them may result in extremely large electric fields (of order 10⁸ V/m) across the intersurface gap. Such large fields can readily affect interfacial phenomena. My talk will describe recent results where interactions between a molecularly smooth mica surface and a gold surface at variable potentials are measured directly, shedding light on different phenomena from the charging dynamics of an individual nanopore to a remarkable control of friction through surface potential changes.