Diego Gutiérrez, Michael Foerster, Ignasi Fina, and Josep Fontcuberta
Daniel Fritsch, Claude Ederer
Phys. Rev. B 86, 125309 (2012)
We have determined the dielectric permittivity of epitaxial CoFe2O4 thin films under different compressive strain states. It is found that the permittivity of structurally relaxed films is similar to that observed for bulk CoFe2O4. In contrast, when the films are compressed, an anomalous reduction of permittivity is observed. First principle calculations have provide some clues for the understanding of this effects.