Atom migration in Pt nanojunctions under electrical stress within the tunneling regime

Abstract We have investigated atom migration at Pt nanojunctions under electrical stress from metallic to tunneling transport regions. In the metallic transport region, atom removal occurs predominantly on the Pt (111) surfaces, on which Pt atoms have a small surface self-diffusion potential, by the kinetic energy transfer from a conduction electron to a Pt atom. In the tunneling region, step-like conductance drops appear at voltages corresponding to the surface self-diffusion potential of Pt (100), (311), (331), and (110) surfaces. These findings demonstrate that electron-induced atomic migration persists even after junction disconnection, providing guidance for defining safe operating voltages in atomic-scale devices.