Interface assisted strain-induced magnetoelectric coupling in core-shell nanostructures of CoFe2O4 @ZnO

Artificially engineered magnetoelectric materials, whose electrical properties can be manipulated by an external magnetic field and vice versa are a new class of materials and find extensive applications in the field of emerging technologies like sensors, electrically controlled spintronic, and microelectronics and memory storage devices. Composites, having ferromagnetic and ferroelectric components are commonly employed where coupling between magnetic and electric fields is relatively weak. It is known that the interface between the components plays a very crucial role for achieving a stronger magnetoelectric (ME) coupling in artificially engineered magnetoelectric materials if the composites are synthesized with a ferro/ferri magnetic core and a ferro/piezoelectric shell. Such core-shell architecture ensures strong interaction and enables better connectivity. In realizing this goal, we report a simple technique to fabricate a core-shell nanostructure consisting of a ferrimagnetic core of CoFe2O4 and a piezoelectric shell of ZnO. The core size is varied and the elastic strain mediated magnetoelectric coupling mechanism through the interface of the core-shell nanostructure is examined.