Enhanced Perpendicular Exchange Bias in Co/Pd Antidot Arrays

Magnetic nanostructures revealing the exchange bias (EB) effect have attracted much interest in recent years due to their promising applications in spintronics, magnetic sensing and recording devices with various functionalities. In this paper, we report on the perpendicular exchange bias effect in a multilayered thin film composed of [Co/Pd] ferromagnetic multilayers exchange-coupled to an antiferromagnetic IrMn. The film was deposited on a porous anodized titania template. Influences of the films’ surface morphology as well as the order of layers deposited on the EB effect were studied. The enhancements of the EB field H EB (up to 30%) and the coercive field H C (two times) were achieved in the nanoporous films relative to their continuous film counterparts, which could be attributed to the specific morphology of the porous surfaces.