Electrical tuning of magnetism is of great fundamental and technical importance for fast, compact and ultra-low power electronic devices. Multiferroics, simultaneously exhibiting ferroelectricity and ferromagnetism, have attracted much interest owing to the capability of controlling magnetism by an electric field through magnetoelectric (ME) coupling. In particular, strong strain-mediated ME in...

We investigate theoretically the ternary copper chalcogenides with the general formula Cu2MMS4. This family of compounds can crystallize in two different non-centrosymmetric structures, I 4̄2m or Pnm21. We show that all the reported members of Cu2MMS4 having the Pnm21 symmetry exhibit a large spontaneous polarization. This result suggests that several of these materials are likely to be multifer...

The multifunctional (ferromagnetic and ferroelectric) response at room temperature that is elusive in single phase multiferroic materials can be achieved in a proper combination of ferroelectric perovskites and ferrimagnetic spinel oxides in horizontal heterostructures. In this work, lead-free CoFe2O4/BaTiO3 bilayers are integrated with Si(001) using LaNiO3/CeO2/YSZ as a tri-layer buffer. They ...

Bismuth oxide (Bi2O3) is an important component of several ferroelectric, 1 multiferroic 2,3 and superconducting oxide materials. 4 It has also received much interest due to its use as an ion conducting electrolyte material in solid oxide fuel cells, 5 an electrode material in discriminating gas sensors 6 and as an effective UV light photocatalyst. 7,8 There are a number of distinct crystallogr...

High-resolution images can be analysed by geometric phase analysis (GPA) [3] or applying peak-finding routines to determine the positions of individual atomic columns. GPA is best adapted to measuring the deformation of the crystalline lattice, as the example concerning a five-fold twinned Pt nanoparticle will show (Figure 1). These star-shaped particles [4] have a disclination-like strain fiel...

Magnetoelectric coupling allows the magnetic state of a material to be changed by an applied electric field. To date, this phenomenon has mainly been observed in insulating materials such as complex multiferroic oxides. Bulk metallic systems do not exhibit magnetoelectric coupling, because applied electric fields are screened by conduction electrons. We demonstrate strong magnetoelectric coupli...

Magnetic spiral structures can exhibit ferroelectric moments as recently demonstrated in various multiferroic materials. In such case the helicity of the magnetic spiral is directly correlated with the direction of the ferroelectric moment and measurement of the helicity of magnetic structures is of current interest. We used soft x-ray resonant diffraction with circular polarized incident radia...

The persisting demand of higher computing power and faster information processing keeps pushing scientists and engineers to explore novel materials and device structures. Within emerging functional materials, there is a focus on multiferroics materials and material-systems possessing both ferroelectric and ferromagnetic orders. Multiferroics with two order parameters coupled through a magnetoel...

In situ Transmission Electron Microscopy (TEM) techniques can potentially fill in gaps in the current understanding interfacial phenomena in complex oxides. Select multiferroic oxide materials, such as BiFeO(3) (BFO), exhibit ferroelectric and magnetic order, and the two order parameters are coupled through a quantum-mechanical exchange interaction. The magneto-electric coupling in BFO allows c...