Ferromagnetic Polarons in Manganites
Abstract
Using the Lanczos method in linear chains we study the double exchange model in the low concentration limit, including an antiferromagnetic super-exchange K. In the strong coupling limit we find that the ground state contains ferromagnetic polarons whose length is very sensitive to the value of K/t. We investigate the dispersion relation, the trapping by impurities, and the interaction between these polarons. As the overlap between polarons increases, by decreasing K/t, the effective interaction between them changes from antiferromagnetic to ferromagnetic. The scaling to the thermodynamic limit suggests an attractive interaction in the strong coupling regime (J_h > t) and no binding in the weak limit (J_h \simeq t).
Keywords
Cite
@article{arxiv.cond-mat/0008367,
title = {Ferromagnetic Polarons in Manganites},
author = {C. D. Batista and J. Eroles and M. Avignon and B. Alascio},
journal= {arXiv preprint arXiv:cond-mat/0008367},
year = {2009}
}
Comments
12 pages, accepted in PRB, to be published in November