Effects of Heterogeneous Strain on the Magnetization Processes in Magnetic Nanomembranes

Abstract

The realization of mechanically compliant spintronic elements relies on magnetic thin films prepared on flexible polymeric foils. Due to the strong difference in the mechanical properties of the magnetic thin film and the polymeric support, strong effects of heterogeneous strain emerge, which govern the magnetic response of the magnetic nanomembrane. Herein, the effect of the heterogeneous strain in a prototypical magnetic nanomembrane of Ni on the application‐relevant polyimide foil is studied. The distribution of the magnetoelastic field in the case of the heterogeneous strain is taken into account and compared with the case of the free‐standing Ni thin film. It is shown that the reversal process is strongly influenced by the heterogeneity at the early stages. Indeed, the reversal is characterized by two modes in the heterogeneous case, due to the strain localization in the nanomembrane, whereas the homogeneous case is characterized by a single mode. In contrast, the strain heterogeneity does not change significantly the postreversal oscillations as well as the equilibrium configuration for a given mean strain. These results are strongly relevant for a broad magnetism community working in the field of curvilinear magnetism, shapeable magnetoelectronics, and straintronics.