Electric field modulation of magnetic properties via magnetoelectric coupling in composite materials is of fundamental and technological importance for realizing tunable energy efficient electronics. Here we provide foundational analysis on magnetoelectric voltage tunable inductor (VTI) that exhibits extremely large inductance tunability of up to 1150% under moderate electric fields. This field dependence of inductance arises from the change of permeability, which correlates with the stress dependence of magnetic anisotropy. Through combination of analytical models that were validated by experimental results, comprehensive understanding of various anisotropies on the tunability of VTI is provided. Results indicate that inclusion of magnetic materials with low magnetocrystalline anisotropy is one of the most effective ways to achieve high VTI tunability. This study opens pathway towards design of tunable circuit components that exhibit field-dependent electronic behavior.

We have performed studies of the orientation distribution in <001>C textured, 0.03(Na1/2Bi1/2)TiO3 ‐ 0.97[0.715Pb(Mg1/3Nb2/3)TiO3 ‐ 0.285PbTiO3] (0.03NBT‐0.97[PMN‐28.5PT]) ceramics by a pole figure method, comparing the results to those for PMN‐PT single crystal and polycrystal samples. The pole figures about the (001) zone are found to have monoclinic, Ma, phase for textured ceramics in the annealed condition and were similar to those for electrically poled single crystals. However, electrical poling of the textured ceramics resulted in a doublet splitting of the orientation distribution about the direction that defined the original grain texturing. Studies of pole figures about other high‐symmetry zones also revealed the development of some degree of preferred orientation along the in‐plane directions after poling. Our findings demonstrate that E‐field induced phase transformation and domain textures superimpose with that of preferred grain orientations, giving rise to a unique texture symmetry for PMN‐PT. The texture symmetry changes are driven by minimization of the elastic strain energy, and have an important effect upon the piezoelectric properties.

A mixed precursor solution method was used to deposit 3-0 nanocomposite thin films of PbZrTiO (PZT) and CoFeO (CFO). The piezoelectric behavior of PZT and magnetostrictive behavior of CFO allow for magnetoelectric (ME) coupling through strain transfer between the respective phases. High ME coupling is desired for many applications including memory devices, magnetic field sensors, and energy harvesters. The spontaneous phase separation in the 3-0 nanocomposite film was observed, with 25 nm CFO particle or nanophases distributed in discrete layers through the thickness of the PZT matrix. Magnetic-force microscopy images of the nanocomposite thin film under opposite magnetic poling conditions revealed in-plane pancake-like regions of higher concentration of the CFO nanoparticles. The constraints on the size and distribution of the CFO nanoparticles created a unique distribution in a PZT matrix and achieved values of ME coupling of 3.07 V cm Oe at a DC bias of 250 Oe and 1 kHz, increasing up to 25.0 V cm Oe at 90 kHz. Piezo-force microscopy was used to investigate the ferroelectric domain structure before and after opposite magnetic poling directions. It was found that in this nanocomposite, the polarization of the ferroelectric domains switched direction as a result of switching the direction of the magnetization by magnetic fields.

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