Magneto-optical imaging of elastic strain-controlled magnetization reorientation

Abstract

We study the validity and limitations of a macrospin model to describe the voltage-controlled manipulation of ferromagnetic magnetization in nickel thin film/piezoelectric actuator hybrid structures. To this end, we correlate simultaneously measured spatially resolved magneto-optical Kerr effect imaging and integral magnetotransport measurements at room temperature. Our results show that a macrospin approach is adequate to model the magnetoresistance as a function of the voltage applied to the hybrid, except for a narrow region around the coercive field-where the magnetization reorientation evolves via domain effects. Thus, on length scales much larger than the typical magnetic domain size, the voltage control of magnetization is well reproduced by a simple Stoner-Wohlfarth type macrospin model. arXiv:1108.3521v1 [cond-mat.mtrl-sci]

Converse magnetoelectric effects in Fe3O4/BaTiO3multiferroic hybrids

“…[4][5][6][7][8][9][10] It has been shown that a robust electric field control of magnetism can be realized by using extrinsic multiferroic hybrid structures consisting of ferroelectric and ferromagnetic materials. [11][12][13][14][15] In these systems, the extrinsic magnetoelectric effects rely on either electric field effects 16 using carrier mediated ferromagnets, 17 or employing exchange coupling effects between antiferromagnetic, ferroelectric and ferromagnetic compounds. 18,19 Moreover, from the beginning the elastic coupling at the interface between ferromagnetic and ferroelectric materials has been exploited to realize a robust electric field control of the magnetization.…”

Fast strain wave induced magnetization changes in long cobalt bars: Domain motion versus coherent rotation

“…Strain driven magnetization reversal of a macroscopic Ni disc on a piezoelectric actuator indicate that the mechanisms for strain driven and field driven magnetization reversal are similar, 20 with short axis magnetization reversal dominated by coherent rotation and easy axis reversal showing domain formation close to the switching strain. In contrast, strain-driven magnetization reorientation in highly magnetostrictive microstructures of thin film FeGa (Ref.…”

Modulation of magnetic coercivity in Ni thin films by reversible control of strain

“…However the application of its antiferromagnetism, instead of ferromagnetism, is still hard to accomplish. Furthermore, the coupling between ferromagnetic metal and ferroelectric oxide, named artificial multiferroics, has currently attracted much attention and actually provides more possibilities for functionality design [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. The coupling between ferromagnetism and ferroelectricity is mediated by the magneto-elastic effect through the reversible electric-field-controlled strain variation [22][23][24][25][26].…”

“…Furthermore, the coupling between ferromagnetic metal and ferroelectric oxide, named artificial multiferroics, has currently attracted much attention and actually provides more possibilities for functionality design [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. The coupling between ferromagnetism and ferroelectricity is mediated by the magneto-elastic effect through the reversible electric-field-controlled strain variation [22][23][24][25][26]. The ferroelectric materials of BaTiO 3 (BTO) [32][33][34][35] and Pb(Zr x Ti x 1− )O 3 (PZT) [26][27][28][29][30][31] have been widely used in the previous studies.…”

“…The coupling between ferromagnetism and ferroelectricity is mediated by the magneto-elastic effect through the reversible electric-field-controlled strain variation [22][23][24][25][26]. The ferroelectric materials of BaTiO 3 (BTO) [32][33][34][35] and Pb(Zr x Ti x 1− )O 3 (PZT) [26][27][28][29][30][31] have been widely used in the previous studies. For example, Lahtinen et al reported on the coupling between ferromagnetic and ferroelectric domains in CoFe/BTO heterostructures [33].…”