Europhys. Lett.
Volume 67, Number 1, July 2004
Page(s) 90 - 95
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 June 2004
Europhys. Lett., 67 (1) , pp. 90-95 (2004)
DOI: 10.1209/epl/i2004-10036-6

Spin-polarized Shockley state at $\chem{Ni(111)}$ free surface and at $\chem{Ni}$- $\chem{Cu}$-based structures on $\chem{Cu(111)}$ surface

L. Magaud1, A. Pasturel2, P. Mallet1, S. Pons1, 3 and J.-Y. Veuillen1

1  LEPES-CNRS - BP 166, 38042 Grenoble cedex 9, France
2  LPM2C-CNRS - BP 166, 38042 Grenoble cedex 9, France
3  IPN, EPFL - 1015 Lausanne, Switzerland

(Received 4 February 2004; accepted in final form 16 April 2004)

The electronic structure of $\chem{Cu(111)}$ and $\chem{Ni(111)}$ free surfaces and of $\chem{Ni}$- $\chem{Cu}$ structures on the $\chem{Cu}$ (111) surface is studied from ab initio calculations. Systems ending on a $\chem{Ni}$ layer are found to be magnetic. The spin splitting of the $\chem{Ni}$ d band raises the position of some minority $\chem{Ni}$ dxz,yz states which then lie in the energy range where the Shockley state should appear. This results in a strong sp- d hybridization of the spin-down components which furthermore depends on the k momentum. As a result, the Shockley state of $\chem{Ni}$-terminated surfaces is spin polarized. The ab initio results are compared to recent STM experiments.

73.20.At - Surface states, band structure, electron density of states.
71.20.Be - Transition metals and alloys.
71.15.Mb - Density functional theory, local density approximation, gradient and other corrections.

© EDP Sciences 2004