Abstract
A band of unbound surface states (resonances), located in an energy region above the vacuum threshold corresponding to an energy band gap in the electron states of the bulk crystal, has been observed by angle-resolved secondary-electron-emission spectroscopy. The experimental dispersion behavior is in agreement with the two-dimensional band structure of a clean (001)W surface recently proposed by Smith and Mittheiss.
- Received 17 January 1977
DOI:https://doi.org/10.1103/PhysRevLett.38.1087
©1977 American Physical Society
