Charge fluctuations and image potential at oxide-metal interfaces

Abstract

We analyze the dynamical response of the Ag metal surface to electronic excitations in a MgO(100)/Ag(100) oxide-metal interface system. Intrinsic and extrinsic surface plasmon excitations are discussed in relation to mutual interactions between the oxide and the metal. A direct relationship is established between the reduction of charge fluctuation energies in the MgO(100) layers and the image charge screening by the Ag(100) metal surface.