Single-atom manipulation mechanisms during a quantum corral construction

We describe a complete picture of how single Ag atoms move on the various potential energy landscapes of an Ag(111) surface during a quantum corral construction by using a scanning tunneling microscope (STM) tip at 6 K. The threshold tunneling resistance and tip-height to move the Ag atom across the surface are experimentally measured as 210+/-19 kOmega and 1.3+/-0.2 A. The experimental atom manipulation signals reveal remarkably detailed atom movement behaviors dependent on the surface crystallographic orientation and offer atomic-level tribology information.