We show that charge ordered rare-earth nickelates of the type RNiO3 (R = Ho, Lu, Pr and Nd) are multiferroic with very large magnetically-induced ferroelectric (FE) polarizations. This we determine from first principles electronic structure calculations. The emerging FE polarization is directly tied to the long-standing puzzle of which kind of magnetic ordering is present in this class of mater...

The kinetics and thermodynamics of first order transitions are universally controlled by defects that act as nucleation sites and pinning centers. Here we demonstrate that defect-domain interactions during polarization reversal processes in ferroelectric materials result in a pronounced fine structure in electromechanical hysteresis loops. Spatially resolved imaging of a single defect center in...

In multiferroic materials, the microscopic magnetic and electric textures are strongly correlated with each other by magnetoelectric (ME) coupling. Therefore, topological dipole textures, such as ferroelectric (FE) skyrmions periodic FE crystals, expected to be induced if ferromagnetic (FM) FM skyrmionic crystals (or lattices so abbreviated SLs for convenience) can stabilized. present work, a q...

Multiferroic heterojunctions are promising for application in low-power storage and spintronics due to their magnetoelectric coupling properties. Controlling the magnetic transport properties of materials by external stimuli then realizing advanced devices constitute key mission this field. We fabricated a multiferroic heterostructure consisting ferroelectric single-crystal (001)-0.7Pb(Mg1/3Nb2...

We have studied the stability of domains and domain walls in multiferroic BiFeO3 thin films using a combination of piezoelectric force microscopy and phase-field simulations. We have discovered that a film-substrate misfit strain may result in a drastically different thermodynamic stability of two parallel domain walls with the same orientation. A fundamental understanding of the underlying phy...

A reversal of magnetization requiring only the application of an electric field can lead to low-power spintronic devices by eliminating conventional magnetic switching methods. Here we show a nonvolatile, room temperature magnetization reversal determined by an electric field in a ferromagnet-multiferroic system. The effect is reversible and mediated by an interfacial magnetic coupling dictated...

There is a growing activity in the search of novel single-phase multiferroics that could finally provide distinctive magnetoelectric responses at room temperature, for they would enable a range of potentially disruptive technologies, making use of the ability of controlling polarization with a magnetic field or magnetism with an electric one (for example, voltage-tunable spintronic devices, unc...

Magnetoelectric coupling is of interest for a variety of applications, but is weak in natural materials. Strain-coupled fibrous composites of piezoelectric and piezomagnetic materials are an attractive way of obtaining enhanced effective magnetoelectricity. This paper studies the effective magnetoelectric behaviors of two-phase multiferroic composites with periodic array of inhomogeneities. For...

Multiferroic composite materials, consisting of coupled ferromagnetic and piezoelectric phases, are of great importance in the drive towards creating faster, smaller and more energy efficient devices for information and communications technologies. Such devices require thin ferromagnetic films with large magnetostriction and narrow microwave resonance linewidths. Both properties are often degra...