Using a first-principles Green's function approach we study magnetic properties of the magnetic binary chalcogenides Bi2Te3, Bi2Se3, and Sb2Te3. The magnetic coupling between transition-metal impurities is long-range, extends beyond a quintuple layer, and decreases with increasing number of d electrons per 3d atom. We find two main mechanisms for the magnetic interaction in these materials: the indirect exchange interaction mediated by free carriers and the indirect interaction between magnetic moments via chalcogen atoms. The calculated Curie temperatures of these systems are in good agreement with available experimental data. Our results provide deep insight into magnetic interactions in magnetic binary chalcogenides and open a way to design new materials for promising applications.
@article{arxiv.1306.6590,
title = {Exchange interaction and its tuning in magnetic binary chalcogenides},
author = {M. G. Vergniory and D. Thonig and M. Hoffmann and I. V. Maznichenko and M. Geilhufe and M. M. Otrokov and X. Zubizarreta and S. Ostanin and A. Marmodoro and J. Henk and W. Hergert and I. Mertig and E. V. Chulkov and A. Ernst},
journal= {arXiv preprint arXiv:1306.6590},
year = {2015}
}