材料期刊网

Using first-principles density functional calculations and the generalized gradient approximation functional including the on-site Coulomb interaction of 4f orbitals, we show that ferroelectricity can be induced by appropriate epitaxial tensile strain in GdN with a simple rock-salt structure, and that the polarization is sensitive to the strain. The calculated phonon spectra of strained GdN also confirm the existence of ferroelectric polarization. In addition, the electronic structure and magnetic properties of strained GdN as a function of strain are investigated. The present work opens up the possibility of epitaxially tensioned GdN thin films as potential multiferroics.