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NiO–Ni composite films were heteroepitaxially grown on (111)-oriented ferroelectric 0.31Pb(In1/2Nb1/2)O3-0.35Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PIN-PMN-PT) single-crystal substrates by pulsed laser deposition. The NiO films prepared in high vacuum are n-type conducting and possess room-temperature ferromagnetism, which originates from oxygen vacancies and the presence of the second Ni phase, respectively. Taking advantage of the electric-field-induced ferroelectric polarization charges, we realized in situ reversible and nonvolatile modulation of both the electrical resistance and magnetism of the film. A relative resistance change of ∼470% is obtained at room temperature, while an appreciable magnetization change of ∼15% was achieved at 50 K by switching the polarization states of PIN-PMN-PT. The coexistence of charge-density-tunable electronic and magnetic properties of NiO–Ni/PIN-PMN-PT heterostructures may provide a strategy to design charge-mediated multiferroic devices for nonvolatile memory and spintronic applications. [ABSTRACT FROM AUTHOR]

We report the structural, dielectric, ferroelectric and magnetic properties of (1- x)BiFe 0.95 Ga 0.03 Mn 0.02 O 3 − x BaTiO 3 (BFGMO− x BTO) lead-free ceramics. Structural characterizations demonstrate that the BFGMO forms single-phase solid solutions with the BTO within the doping level of x = 0.3–0.65. With increasing the content of BTO the dielectric constant and ferroelectric Curie temperature shift towards lower temperatures, exhibiting relaxor-like ferroelectric behaviors. Moreover, the remnant polarization reaches the maximum value of 2 P r ~27.67 μC/cm2 at x = 0.35 near the morphotropic phase boundary. At room temperature, remnant magnetization increases - to the maximal value of 2 M r ~0.584 emu/g at x = 0.45, which is attributed to local lattice distortion and destruction of the spiral antiferromagnetic spin structure upon the doping of BTO. The coexistence of ferroelectric and ferromagnetic performance at room temperature makes the environment-friendly BFGMO− x BTO ceramics potential candidate for multiferroic device applications. [ABSTRACT FROM AUTHOR]

• In situ reversible tuning of resistance is achieved in LaMnO 3 /PMN-PT(0 1 1) structure. • Non-180° domain switching-induced strain causes nonvolatile resistance tuning. • In-plane tensile stain contributes to the weakened magnetization. The electric-field control of resistance change (Δ R / R) and magnetic properties has been investigated in the LaMnO 3 (LMO)/0.71Pb(Mg 1/3 Nb 2/3)O 3 -0.29PbTiO 3 (PMN-PT)(0 1 1) heterostructure. When the unipolar electric field (E) increases beyond the coercive field of PMN-PT, the Δ R / R vs E curve transforms from a loop-like behavior to a butterfly-like one. The electric-field-induced non-linear strain effect in the PMN-PT substrate realizes the modulation between low and high resistance states at room temperature. Moreover, different freezing temperatures of the LMO film are observed as the PMN-PT substrate is in the fully negative (P r -) and partially positive (P r / / ) polarization states. The observation of less magnetization for P r / / state than that for P r - state indicates that the in-plane tensile strain is beneficial to the Jahn-Teller distortion. [ABSTRACT FROM AUTHOR]