Europhys. Lett.
Volume 73, Number 2, January 2006
Page(s) 239 - 245
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 09 December 2005
Europhys. Lett., 73 (2), pp. 239-245 (2006)
DOI: 10.1209/epl/i2005-10381-x

Two-state behaviour of Kondo trimers

M. E. Torio1, K. Hallberg2 and C. R. Proetto2

1  Instituto de Física Rosario, CONICET-UNR Bv. 27 de Febrero 210 bis, 2000 Rosario, Argentina
2  Centro Atómico Bariloche and Instituto Balseiro, CNEA 8400 Bariloche, Argentina

received 15 September 2005; accepted in final form 18 November 2005
published online 9 December 2005

The electronic properties and spectroscopic features of a magnetic trimer with a Kondo-like coupling to a non-magnetic metallic substrate are analyzed at zero temperature. The substrate density of states is depressed in the trimer neighbourhood, being exactly zero at the substrate chemical potential. The size of the resonance strongly depends on the magnetic state of the trimer, and exhibits a two-state behavior. The geometrical dependence of these results agree qualitatively with recent experiments and could be reproduced in a triangular quantum dot arrangement.

73.22.-f - Electronic structure of nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals.
75.75.+a - Magnetic properties of nanostructures.
75.25.+z - Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source X-ray scattering, etc.).

© EDP Sciences 2006