From first principles calculations we investigate the electronic structure and the magnetic properties of EuO under hydrostatic and epitaxial forces. There is a complex interdependence of the O 2p and Eu 4f and 5d bands on the magnetism in EuO, and decreasing lattice parameters is an ideal method to increase the Curie temperature, T_c. Compared to hydrostatic pressure, the out-of-plane compensation that is available to epitaxial films influences this increase in T_c, although it is minimized by the small value of poisson's ratio for EuO. We find the semiconducting gap closes at a 6% in-plane lattice compression for epitaxy, at which point a significant conceptual change must occur in the active exchange mechanisms.
@article{arxiv.0711.4586,
title = {Epitaxial influence on the ferromagnetic semiconducotor EuO},
author = {N. J. C. Ingle and I. S. Elfimov},
journal= {arXiv preprint arXiv:0711.4586},
year = {2008}
}