Effect of Co interlayers in Fe/MgO/Fe magnetic tunnel junctions

Abstract

The effect of Co interlayers in -Fe(001)/Co/MgO/Co/Fe- magnetic tunnel junctions is studied by first-principles calculation. We confirm that the Co layers inserted at the two Fe/MgO interfaces strongly influence the interfacial resonance (IR) states and the tunneling magnetoresistance (TMR). The effect is not monotonic. Strongest IR occurs at Co layer thickness of 0.5 monolayer (ML). With 1 ML Co, the IR is dramatically reduced and TMR ratio is maximized. © 2008 American Institute of Physics.