Analytical prediction of size-induced ferroelectricity in BaO nanowires under stress

We predict that a ferroelectric phase can be induced in otherwise nonferroelectric binary oxides like BaO, EuO and Er2O3 by a strong enough stress sigma similar to mu/R present under the curved surface in nanowires due to intrinsic surface stress mu. Our analytical calculations performed within the Landau-Ginzburg-Devonshire theory prove that BaO nanowires of radius R similar to(1-10) nm can be ferroelectric at room temperatures with spontaneous polarization values similar to 0.5 C/m(2) for typical surface stress coefficients mu similar to(10-50) N/m. The same phenomena could lead to high temperature magnetoelectric effect in nanosystems of magnetic binary oxides.