Unaltered reversible magnetic transition in Fe nanostructures upon ambient exposure

摘要

Highlights ? 20–30nm thin Fe strips grown on Ru(0001). ? Reversible transition from single to multi-domain magnetic structure reproduced. ? Transition unaltered after exposing the uncapped nanostructures to air for 30min. ? 2–5nm thin oxide surface layer forms that prevents further oxidation. Abstract High aspect-ratio Fe nanostrips are known to reversibly switch from a single-domain magnetic state to a multidomain diamond pattern as a function of temperature (T) and width. This magnetic bistability can be understood by the temperature-dependent balance between magnetocrystalline, shape and magnetoelastic anisotropies and has potential applications in magnetic logic devices. However, as Fe nanostructures easily oxidize, protecting the surface with capping layers may be required, which could largely affect the anisotropy balance. Here, we employ x-ray magnetic circular dichroism-photoemission electron microscopy (XMCD–PEEM) to study these thin Fe nanostrips before and after exposure to air. ]]>