Control Of The Magnetization Dynamics In Magnetostrictive Nanostructures Through The Magneto-Elastic Coupling Effect

The magneto-elastic (ME) coupling has attracted an increasing interest in the last years, in particular for micro- and nanostructured magnetostrictive materials. The magnetic configuration of these materials can be controlled by mechanical strain (generated e.g. with a piezoelectric substrate), an example of which is the strain induced anisotropy in Ni nanostructures. However, while the quasi-static properties of the ME coupling have been thoroughly investigated, an analysis of the influences of the ME coupling on the magnetization dynamics is still lacking, in part due to the experimental difficulties involved in the use of piezoelectric substrates. Here, we present an alternative path to the use of piezoelectric materials for the investigation of the effect of the ME coupling on magnetization dynamics with time-resolved x-ray magnetic microscopy. With this approach, the magnetostrictive elements are strained by the bending of a thin SiN membrane in-situ, through the generation of a pressure difference between the two sides of the membrane. This is achieved by employing a pressure controlled environmental cell. Using SiN membranes with different geometries, the direction of the applied strain can be tuned, allowing for the generation of a pressure-controlled uniaxial magnetic anisotropy in microstructured Ni elements. Furthermore, this additional ME anisotropy also strongly influences the magnetization dynamics of the Ni structures, thus demonstrating that our approach provides a simple and powerful tool for the analysis of the magnetization dynamics in magnetostrictive elements.