ATOMIC SWITCH PROVES IMPORTANCE OF ELECTRON-HOLE PAIR MECHANISM IN PROCESSES ON METAL-SURFACES

A mechanism is proposed for the recently developped atomic switch, an atomic-scale electronic device, whose operation is controlled by the displacement of a Xe atom between a Ni(110) surface and a W tip of a scanning-tunneling microscope. Its key ingredient is that the electrons participating in the current through the switch excite the Xe atom vibrationally in a double well, sustained by the attraction to both surface and tip, and transfer it to the other well. This theory accounts for the observed facts and provides additional, easily testable, predictions. The atomic switch thus gives an experimental proof of the electron-hole pair mechanism for the energy transfer in dynamical processes at metal surfaces.