Spin-filter effect at the interface of magnetic/non-magnetic homojunctions in Li doped ZnO nanostructures

After more than a decade of extensive research on the magnetic order triggered by lattice defects in a wide range of nominally non-magnetic materials, we report its application in a spintronic device. This device is based on a spin-filter phenomenon we discovered at the interfaces between defect-induced magnetic and non-magnetic regions, produced at the surface of a Li doped ZnO microwire by low-energy proton implantation. Positive magnetoresistance is observed at 300~K and scales with the number of interfaces introduced along the wire.