Tunneling Spectroscopy Characteristics of bcc(001) Surfaces
Abstract
With a few exceptions, tunneling conductance spectra of metals lack unique spectroscopic features as compared to spectra of semiconductor surfaces. Using scanning tunneling spectroscopy, we have identified a sharp conductance peak near the Fermi energy on both Fe(001) and Cr(001) surfaces. The peaks are narrow with widths comparable to the thermal broadening and are centered at 0.17 eV above Ef for Fe and at 0.05 eV below Ef for Cr. Band structure calculations show that this peak is due to a Shockley-like surface state, arising from a highly-localized atomic orbital of mainly d_z^2 symmetry. The state originates from the s-d hybridization (symmetry) gap and can be found on many bcc(001) transitional metal surfaces. For Cr and Fe, the surface state is in the minority spin band and will be useful in spin-polarized tunneling measurements. \vspace12pt * This work is supported in part by the Office of Naval Research.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1996
- Bibcode:
- 1996APS..MAR.G1606D