The direct magnetoelectric (ME) effect mediated by lattice strains induced in a ferroelectric film by a ferromagnetic substrate is evaluated using first-principles-based calculations. To that end, the strain sensitivity of ferroelectric polarization and the film permittivity are calculated as a function of the in-plane biaxial strain for Pb(Zr${}_{0.52}$Ti${}_{0.48}$)O${}_3$ films under various depolarizing fields. It is found that the ME voltage coefficient varies nonmonotonically with this strain and may reach giant values exceeding 100 V cm${}^{-1}$ Oe${}^{-1}$ over a strain range that can be controlled through the electrical boundary conditions.

• Received 21 September 2011

DOI:https://doi.org/10.1103/PhysRevB.85.140401