Periodic arrays of micrometer and sub-micrometer magnetic structures prepared by nanoindentation of a nonmagnetic intermetallic compound

Periodic arrays of magnetic structures were prepared by nanoindentation, in a single step by taking advantage of the property of certain nonmagnetic intermetallic compounds to become ferromagnetic, when subjected to plastic deformation or ion irradiation. The magnetic properties of the intermetallic compound was also investigated by means of a magneto-optical Kerr effect (MOKE) setup. The nanoindentation method is based on the selective generation of atomic disorder and other types of materials such as austenitic stainless steel. The local character of the ferromagnetism induced by nanoindentation was examined by magnetic force microscopy (MFM). Dark and bright areas were observed inside the indentations, indicating a multi-domain structure. MFM clearly confirmed that ferromagnetism was locally induced by the nanoindentation experiments, and can be erased by subjecting the locally deformed sheets to annealing process.