Dielectric, electrical and magnetoelectric characterization of (x)Ni_(0.8)Zn_(0.2)Fe_2O_4 + (1 - x)Pb_(0.93)La_(0.07)(Zr_(0.60)Ti_(0.40)O_3 composites

摘要

The structural, electrical, dielectric, magnetic and magnetoelectric properties of (x)Ni_(0.8)Zn_(0.2)-Fe_2O_4 + (1- x)Pb_(0.93)La_(0.07)(Zr_(0.60)Ti_(0.40)O_3 (x = 0, 0.15, 0.30, 0.45 and 1) have been studied by means of various experimental techniques. Polycrystalline samples of this series have been prepared by the double sintering ceramic method. X-ray diffraction data analysis revealed purity of the composites. Microstructural analysis using scanning electron microscopy mode depicts the presence of two phases in contact with each other. Dielectric properties were studied at and well above room temperature. Temperature dependent variation of the dielectric constant show diffused phase transition which can be well described by fitting the Lorentz-type relation,ε_A/ε = 1 + (T-T_A)~2/2δ_A~2. Observation of well-saturated ferroelectric hysteresis loop and magnetic hysteresis loop for composites indicates that ferroelectric and magnetic ordering exist simultaneously at room temperature. The static value of magneto electric voltage coefficient (α_E) has been studied as a function of magnetic field at room temperature for all the composites. The maximum value of α_E is 7.53 mV/(cm Oe) for 85% PLZT-15% NZFO composites.