Crystalline aluminum substituted yttrium iron garnet nanoparticles Y 3 Fe 3.35 Al 1.65 O 12 (YIG) was synthesized by hydrothermal microwave synthesis at 140 °C with soaking times ranging from 15 to 60 min. X-ray diffraction confirmed the single-phase YIG nanoparticles excluding the presence of any other phases in the reaction products. The Raman spectra revealed that the largest soaking time provides greater energy crystallization causing changes of lattice vibration and a certain degree of disorder in the crystal lattice. Field emission gun-scanning electron microscopy and high resolution transmission electronic microscopic revealed a homogeneous size distribution of nanometric YIG powders with agglomerated particles. Magnetic measurements were achieved by using a vibrating-sample magnetometer unit. YIG nanoparticles have great potential in magneto-hyperthermia application once in vivo applications magnetic induction heating ferromagnetic compounds generate heat in AC magnetic fields.

BiFeO 3 (BFO) and LaFeO 3 (LFO) heterostructures were obtained at room temperature on Pt/TiO 2 /SiO 2 /Si (100) substrates by chemical solution deposition. The films were coherently grown at a temperature of 500°C for 2 hours. The magnetoelectric coefficient measurement was performed to show magnetoelectric coupling behavior of such heterostructures. The bottom BFO layer in the heterostructure was able to promote the grain growth of the LFO during the annealing process resulting in huge crystal size. Dielectric permittivity and dielectric loss measurements demonstrated only slight dispersion with frequency due to the lower two-dimensional stress in the plane of the film. Improvement of the P-E hysteresis loop was observed for the heterostructure due the decrease of leakage current caused by the LFO sublayer. Room temperature magnetic coercive field measurements indicate that the LFO and LFO/BFO present different magnetic behavior. The magnetic behavior of the heterostructure is influenced by the crystallite size.

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Atomic Force Acoustic Microscopy (AFAM) and Piezoresponse Force Microscopy (PFM) were used to study local elastic and electromechanical response in BaTiO 3 ceramics. A commercial multi-mode Scanning Probe Microscopy (SPM) and AFAM mode to image contact stiffness were employed to accomplish the aforementioned purposes. Stiffness parameters along with Young's moduli and piezo coefficients were quantitatively determined. PFM studies were based on electrostatic and electromechanical response from localized tip-surface contact. Comparison was made regarding the Young's moduli obtained by AFAM and PFM. In addition, phase and amplitude images were analyzed based on poling behavior, obtained via the application of −10 V to +10 V local voltage.

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