Observation of ferri-nonmagnetic boundary in CrPt3 line-and-space patterned media using a dark-field transmission electron microscope

► Dark field transmission electron microscope observation to study the bit boundary of the ion beam patterned CrPt3 film. ► Clear contrast between non-irradiated (L12 phase CrPt3) and irradiated (A1 phase CrPt3) regions in the image. ► The transition width between the two phases is about 5 nm. ► The estimated width agrees well with the simulation.