Interface and thickness effect of mechanical and magnetic properties of low dimensional structure
Low dimensional structures, such as thin film and multilayer systems, show very interesting physical behaviors not show in bulk materials. In this project, we will investigate magnetic and mechanical properties of low dimensional systems. The dislocation motion is essential factor to determine the strength of the metals. The higher strength has been observed in metal multilayer with nanolayed composite such as Cu/Nb, Graphene/Cu, and Graphene/Ni multilayer systems. This enhancement comes from incoherence interface and resistance against dislocation propagation across the interface. We will investigate the effect of interface (coherence and incoherence) and thickness of metal layers in dislocation motion to understand high strength materials. It will provide pictures of application of grain boundary engineering.
In addition, we will study magnetic and magnetoelastic properties of thin film and multilayer systems. The change of magnetic anisotropy energy (MAE) induced by strain should be obtained to understand magneto-elastic coupling. Most research have focused bulk alloys such as, FeGa, MnGa, FeBe, and NiMnGa alloys, although magnetism in nanoscale materials is receiving much more important research interest due to both fundamental interest and novel magnetic applications. It will be studied strain dependent magnetic properties of polycrystalline metal and heterostructure, such as metal/Graphene/metal, metal/topological insulator/metal and metal/semiconductor/metal. The polycrystalline metal and heterostructure are possible to show unusual behavior of magnetic anisotropy under external strain. It is expect that magnetic properties, such as magnetic interaction between magnetic layers and MAE can be controlled by external strain in layered and heterostructures.