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This paper presents numerical and experimental data for dipole-dipole coupled Ni nanodots on a piezoelectric [Pb(Mg1/3Nb2/3)O3]0.68[PbTiO3]0.32 substrate. Simulation results show that the dipole coupling produces artificial ferromagnetic (parallel magnetization alignment in the nanodot arrays) behavior that can be modified to artificial antiferromagnetic behavior with an applied voltage. Experimental results show the trends in Mr and Hc predicted by the model, but discrepancies arise due to geometric defects present in the fabricated samples. Geometric defects are introduced into the Ni nanodot models, thus dramatically improving the correlation between experiments and analysis. This work shows, through numerical simulations, that artificial multiferroic nanostructures can be designed to produce switching from parallel (artificial ferromagnetic) to antiparallel (artificial antiferromagnetic) magnetization ordering by leveraging dipole coupling with voltage induced changes in magnetic anisotropy. [ABSTRACT FROM AUTHOR]

We report strain-induced coercive field changes in patterned 300 × 100 × 35 nm3 Ni nanostructures deposited on Si/SiO2 substrate using the magnetoelastic effect. The coercive field values change as a function of the applied anisotropy strain (∼1000 ppm) between 390 and 500 Oe, demonstrating that it is possible to gradually change the coercive field elastically. While the measured changes in coercive field cannot be accurately predicted with simple analytical predictions, fairly good agreement is obtained by using a micromagnetic simulation taking into account the influence of nonuniform strain distribution in the Ni nanostructures. The micromagnetic simulation includes a position dependant strain-induced magnetic anisotropy term that is computed from a finite element mechanical analysis. Therefore, this study experimentally corroborates the requirement to incorporate mechanical analysis into micromagnetic simulation for accurately predicting magnetoelastic effects in patterned ferromagnetic nanostructures. [ABSTRACT FROM AUTHOR]