Tunable Strain in Magnetoelectric ZnO Micro Rod Composite Interfaces.

The intrinsic strain at coupled components in magnetoelectric composites plays an important role for the properties and function of these materials. In this in situ X-ray nanodiffraction experiment the coating induced as well as the magnetic field induced strain at the coupled interface of complex magnetoelectric micro composites were investigated. These consist of piezoelectric ZnO micro rods coated with an amorphous layer of magnetostrictive (Fe90Co10)78Si12B10. While the intrinsic strain is in the range of 10(-4), the magnetic field induced strain is with 10(-5) one order of magnitude smaller. Additionally, the strain relaxation distance of around 5 μm for both kinds of strain superposes indicating a correlation. The value of both intrinsic and magnetic field induced strain can be manipulated by the diameter of the rod like composite. The intrinsic interface strain within the ZnO increases exponentially by decreasing the rod diameter while the magnetic field induced strain increases linear within the given range.