Giant magnetocapacitance of strained ferroelectric-ferromagnetic hybrids

N. Pertsev (1, 2) , S. Prokhorenko (2) , B. Dkhil (2)

1 IAP - A.M.Obukhov Institute of Atmospheric Physics
2 SPMS - Laboratoire Structures, Propriétés et Modélisation des solides

We report a theoretical calculation of the strain-mediated magnetocapacitance of ferroelectric-ferromagnetic heterostructures. Our nonlinear theory predicts that this magnetocapacitance strongly depends on the strain state of a ferroelectric constituent. For multiferroic hybrids comprising a BaTiO3 or Pb(Zr0.5Ti0.5)O3 film and a FeBSiC, Terfenol-D, or FeGa substrate, the magnetocapacitive coefficient generally has a giant value ∼10−4 Oe−1. Remarkably, its magnitude further increases drastically near the strain-induced phase transition at which the out-of-plane polarization appears in the ferroelectric film. As a result, the magnetocapacitance of hybrids including Terfenol-D may exceed 100% already at the magnetic field of about 600 Oe. These theoretical results provide guidelines for the fabrication of multiferroic heterostructures exhibiting a strong magnetodielectric effect.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

N. Pertsev, S. Prokhorenko, B. Dkhil. Giant magnetocapacitance of strained ferroelectric-ferromagnetic hybrids. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012, 85, pp.134111. ⟨10.1103/PhysRevB.85.13411⟩. ⟨hal-00762120⟩