English

Band-filling effects on the Kondo-lattice properties

Strongly Correlated Electrons 2009-11-07 v1

Abstract

We present theoretical results for a Kondo-lattice model with spin-1/2 localized moments, including both the intrasite Kondo coupling and an intersite antiferromagnetic exchange interaction, treated within an extended mean-field approximation. We describe here the case of a non-integer conduction-band filling for which an ``exhaustion'' problem arises when the number of conduction electrons is not large enough to screen all the lattice spins. This is best seen in the computed magnetic susceptibility. The Kondo temperature so obtained is different from the single-impurity one, and increases for small values of the intersite interaction, but the Kondo-effect disappears abruptly for low band filling and/or strong intersite coupling; a phase diagram is presented as a function of both parameters. A discussion of experimental results on cerium Kondo compounds is also given.

Keywords

Cite

@article{arxiv.cond-mat/0212034,
  title  = {Band-filling effects on the Kondo-lattice properties},
  author = {B. Coqblin and C. Lacroix and M. A. Gusmão and J. R. Iglesias},
  journal= {arXiv preprint arXiv:cond-mat/0212034},
  year   = {2009}
}

Comments

9 pages, 8 figures, to appear in Phys Rev B (1 february 2003)