Original design of a patterned multiferroic heterostructure for electrical control of the magnetic shape anisotropy

In the framework of piezoelectric/ferromagnetic patterned heterostructures, the purpose of this work is to electrically control the magnetic properties by tuning the morphology, especially by modifying the magnetic shape anisotropy through patterned strain. We have thus designed and studied a heterostructure with bottom nano-striped and top full film electrodes. ZnO piezoelectric and CoFeB magnetic materials were chosen to respond at critical criteria of its geometry. In addition, numerical simulations and magnetostatic calculations were performed to understand the reproduction of the pattern across the multiferroic heterostructure. Calculations have shown that the geometry of the heterostructure presents strict constraints, as for instance the distance between stripes versus the piezoelectric thickness. This study is a preliminary step towards reversible patterning of magnetic properties.