Confinement of surface state electrons on Cu and Au field emitters.
Field-emission images of clean Cu and Au emitters show a peculiar halo-like ring centered at the [1 1 1] pole. Typical diameter and width of the ring are approximately 10 nm and approximately 2 nm, respectively. Since we found no geometrical features around the [1 1 1] pole that gives rise to such a ring pattern, we interpreted the ring pattern as representing enhanced emission from an annular terrace that resonantly confines surface electrons. A simple analysis shows that the observed ring pattern appears at a terrace whose width nearly matches the confinement condition.
Sakata
T
T
Department of Integrated Arts and Sciences, University of Osaka Prefecture, Japan. sakai@mesostm.mtl.kyoto-u.ac.jp
Fujioka
H
H
Sakai
A
A