Investigation of the Perpendicular Exchange Bias in the Cu/Ni/FeMn Structure

Abstract

The perpendicular exchange bias (Hex) in epitaxial Cu/Ni/FeMn trilayers with various Ni and FeMn thicknesses has been investigated. All the samples were prepared by dc-magnetron sputtering. We analyzed the behaviors of the exchange bias eld and the coercivity as functions of the Ni and the FeMn thicknesses. The maximum perpendicular exchange bias eld (305 Oe) was obtained for Ni(4 nm)/FeMn(5 nm) lms. The exchange bias energy, ex, was calculated in a good argument that exchange bias eld depends on Ni thickness. The crystalline orientation is also reported.