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We report an enhanced magnetodielectric (MD) coupling in antiferromagnetic Bi2Fe4O9(BFO) lightly substituted by gadolinium (Gd3+).

The investigation of charge ordering (CO) suppression and consequence effects in manganites are of interest to the scientific community as they help them to understand the interactions among the spin, charge and orbital degrees of freedom of conduction electrons. In this work, the suppression of CO in small bandwidth half‐doped manganite, Nd0.5Ca0.5MnO3 (NCMO) has been demonstrated by reducing the particle size. Bulk and nano forms of NCMO materials are prepared by sol‐gel technique and characterized by various physicochemical techniques. The magnetic and magnetotransport properties of bulk samples show the exciting features, viz., CO, training and irreversible metamagnetic effects, whereas these features are significantly suppressed in the nanoscale sample. The observed behavior in the present investigation is explained in terms of magnetic phase separation and spin memory effects. Our investigation establishes a combined effect of surface spin disorder and lattice strains for the suppression of CO behavior in NCMO manganite system.

Electric field controlled magnetism is an exciting area of condensed matter physics to explore the device applications at ultra-low power consumption compared to the conventional current controlled or magnetic field controlled devices. In this study, an attempt was made to demonstrate electric field controlled magnetoresistance (MR) in a tri-layer structure consisting of La0.67Sr0.33MnO3 (LSMO) (40 nm)/SrTiO3 (10 nm)/LSMO (10 nm) grown on a 500-μm-thick BaTiO3 (001) (BTO) single crystal substrate by pulsed laser deposition technique. Epitaxial growth of the trilayer structure was confirmed by x-ray diffraction measurements. Jumps observed in the temperature-dependent magnetization curve at around the structural phase transitions of BTO ensure the strain-mediated magnetoelectric coupling between LSMO and BTO layers. A significant change in MR of this structure in applied electric fields does not show any polarity dependence. The findings are related to the lattice strain-mediated magnetoelectric coupling in ferromagnetic LSMO/ferroelectric BTO heterostructures.

Magnetization reversal has been demonstrated in an Fe layer grown on BaTiO3(110) single crystal substrate by utilizing the interface magnetic anisotropy induced by lattice strain and a small magnetic field bias. The polar plots of normalized remanent magnetization show isotropic nature at room temperature (293 K), while those at 230 and 175 K exhibit twofold symmetry with the easy axis oriented along [‐111]pc of BaTiO3. Cooling and heating cycles in the range of 150–325 K in an applied magnetic field of −35 Oe along [‐111]pc enable to achieve the deterministic 180° magnetization reversal, where distinct magnetic anisotropies of Fe associated with different structural phases of BaTiO3 will be the driving force that induces the magnetization reversal. Electric field dependence of the magnetic coercivity shows hysteric behavior, which we attribute to the combined interfacial effect of magnetization rotation in Fe and ferroelectric polarization switching in BaTiO3.