Abstract
Scanning tunneling microscopy at 4 K shows highly anisotropic screening charge density oscillations on in the vicinity of surface defects and steps. The forms of these oscillations, which derive from the Friedel oscillations, can be directly related to the two-dimensional band structure of the surface (two electron pockets at the boundary of the surface Brillouin zone). Simple calculations show that the Friedel oscillations in such a case will contain major contributions from wavelengths which do not correspond to any Fermi wave vector.
- Received 13 December 1996
DOI:https://doi.org/10.1103/PhysRevLett.79.265
©1997 American Physical Society