Magnetoelectricity in Piezoelectric/Magnetostrictive Nanocomposites at Microwave Frequencies

We present a comprehensive study of the magnetic and microwave properties of piezoelectric BaTiO₃ /magnetostrictive Ni nanocomposites (NCs), fabricated under uniaxial compression, at room temperature. In the current work, we investigated samples in function of magnetic phase content in a piezoelectric matrix and from 6 to 28 GHz using broadband ferromagnetic resonance (FMR-stripline) experiments in the microwave regime in combination with atomic (AFM) and magnetic force microscopy (MFM), X-ray diffraction (XRD), electron transport, and broadband (0.1-6 GHz) microwave spectroscopy experiments to correlate magnetization dynamics properties, electromagnetic materials parameters, and microstructural information to the magnetoelectric (ME) coupling coefficient. We provide the experimental evidence for ME effect, i.e., the effective permittivity at microwave frequencies can be controlled by an external magnetic field, which makes these nanostructures ready for microwave tunable devices, sensors, and transducers.