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arXiv · 0711.4586

Epitaxial influence on the ferromagnetic semiconducotor EuO

N. J. C. Ingle·I. S. Elfimov
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Abstract

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.

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N. J. C. Ingle, I. S. Elfimov. 2007-11-28. Epitaxial influence on the ferromagnetic semiconducotor EuO. https://doi.org/10.1103/physrevb.77.121202

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