English

Limited influence of diluted ferromagnetic dimers on Curie temperature in complex magnetic systems

Strongly Correlated Electrons 2010-08-20 v1

Abstract

In this work we investigate Ising and classical Heisenberg models for two and three dimensional lattices in presence of diluted ferromagnetic dimers. For such models the Curie temperature as a function of ratio of intra-dimer exchange coupling constant I_A and other inter-site coupling constants I_B is calculated. In case dimer is treated exactly and environment within the mean-field approach it was found that even for I_A/I_B\to\infty T_C remains finite. Similar analysis is proposed for rhombohedral phase of intermetallic compound Gd2Fe17 where so-called Fe1-Fe1 "dumbbell" forms the diluted ferromagnetic dimer. It was shown that for such complex magnetic systems T_C is determined by all variety of exchange interactions and for the interval 0 < I_A/I_B < \infty T_C changes are not more than +/-10%.

Keywords

Cite

@article{arxiv.1008.3219,
  title  = {Limited influence of diluted ferromagnetic dimers on Curie temperature in complex magnetic systems},
  author = {M. V. Medvedev and I. A. Nekrasov},
  journal= {arXiv preprint arXiv:1008.3219},
  year   = {2010}
}

Comments

8 pages, 5 figures, 3 tables