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We report structural, dielectric, ferroelectric, magnetic, and low frequency magnetoelectric (ME) properties of (1−x) Bi0.5Na0.5TiO3 (BNT)–xNi0.5Zn0.5Fe2O4 (NZFO) (x = 0.05–0.30) microwave sintered particulate composites. Distinct phases of BNT and NZFO were confirmed by X-ray diffraction and scanning electron microscopy. Raman spectroscopy measurement showed the absence of micro-strains within the composite. The temperature dependent dielectric studies revealed the ferroelectric to anti-ferroelectric transition at 220 °C and anti-ferroelectric to paraelectric transition at 320 °C. The ac conductivity showed both frequency dependent and independent behavior. Temperature dependent dc conductivity showed that upto 200 °C charge conduction is due to hopping of electrons, whereas at higher temperature diffusion of oxygen vacancies are responsible for the conduction. Ferroelectric and leakage current density measurements showed enhanced conduction losses with NZFO content. The maximum ME coefficient at 10 Hz frequency is obtained for 0.80BNT–0.20NZFO (4.33 mV/cm.Oe at 800 Oe). [ABSTRACT FROM AUTHOR]

In this work, heteroepitaxial Bi0.90La0.10Fe0.95Mn0.05O3 (BLFMO) thin films have been grown on Si (100) substrate using LaNiO3/CeO2/Y0.08Zr0.92O3 buffer layers and on SrTiO3 (STO) substrate using pulsed laser deposition. SrRuO3 (SRO) has been used as a bottom electrode in both cases. AC conductivity analysis reveals that BLFMO films deposited on SrTiO3 (STO) substrate are governed by translational hopping, while those deposited on Si are governed by relocalized reorientation hopping. Also, films on STO have DC conductivity dominance over the low frequency range. The remnant polarization for the films deposited on Si and STO is 24 and 66 µC/cm2, while the coercive field is 280 kV/cm and 251 kV/cm, respectively. Impedance and modulus analysis reveals that both the samples show electrical heterogeneity. The leakage current mechanism can be well explained using space charge limited current (SCLC) and Fowler–Nordheim (FN) conduction mechanism for films deposited on all substrates. Films deposited on STO have Schottky behavior at low field and SCLC and FN tunneling current mechanism. [ABSTRACT FROM AUTHOR]

The solid solution of 0.67% Bi0.95La0.05FeO3–0.33% BaTiO3 (BLF–BT) was made by the sol–gel method. The sample's structural, microstructural, and electrical properties were investigated by XRD, SEM, and dielectric measurement, respectively. The BLF–BT shows insulating behavior as revealed from the complex impedance analysis and AC conductivity analysis. The sintered BLF–BT shows relative permittivity of the order of – 106 at high temperatures and follows the Maxwell–Wagner relaxation. Two charge carrier species were responsible for the relaxation process at low and high temperatures. The conduction in the sample is explained with the help of the jump relaxation model (JRM). Room temperature AC conductivity of the BLF–BT samples was observed to be – 10−7 S/cm, lower than that reported in literature. Impedance and modulus analysis was carried out to find out the conduction mechanism. The complex modulus analysis shows almost equal grain and grain boundary capacitances (variation in capacitance is of the order of – 2) in comparison to the resistances (variation in resistance is of the order of – 8). Further, leakage current mechanism is dominated by space charge-limited conduction (SCLC) in our BLF–BT ceramics. [ABSTRACT FROM AUTHOR]

The effect of sintering temperature (Ts) on the phase formation, structural, multiferroic, and magnetoelectric properties of BaTi0.975Fe0.025O3 (BTFO) ceramics has been investigated. The samples have been prepared via a solid-state reaction route and sintered at various temperatures between 1200 °C and 1350 °C. Detailed X-ray diffraction (XRD) analysis confirms a perovskite structure with a tetragonal phase except for the samples sintered at 1350 °C where coexistence of tetragonal and hexagonal phase is observed. The hexagonal phase of the BTFO sample sintered at 1350 °C degrades the electrical properties. All compositions exhibit ferromagnetic behavior, as seen from the M-H curves. Magnetodielectric coefficient (MD) and Magnetoelectric (ME) voltage coefficient α ME have been measured to confirm the intrinsic magnetoelectric behavior. [ABSTRACT FROM AUTHOR]