  Double ring formation on Co2MnSi (CMS) films is observed at electrical
breakdown voltage during local anodic oxidation (LAO) using atomic force
microscope (AFM). Corona effect and segregation of cobalt in the vicinity of
the rings is studied using magnetic force microscopy and energy dispersive
spectroscopy. Double ring forma-tion is attributed to the interaction of
ablated material with the induced magnetic field during LAO. Steepness of
forward bias transport characteristics from the unperturbed region of the CMS
film suggest a non equilibrium spin contribution. Such mesoscopic textures in
magnetic films by AFM tip can be potentially used for memory storage
applications.
