Interface Engineering Towards Enhanced Exchange Interaction Between Fe And Feo In Fe/Mgo/Feo Epitaxial Heterostructures

In our study, we examined the chemical and magnetic properties of FeO in an epitaxial Fe/MgO(d(MgO))/FeO trilayer for different MgO thicknesses, d(MgO). Analysis of the chemical structure revealed a stoichiometry improvement in the FeO layer in Fe/MgO/FeO in comparison with a Fe/FeO bilayer. Furthermore, we showed that deposition of a subtle MgO layer at the Fe/FeO interface results in an enhanced exchange interaction between Fe and FeO. For d(MgO) = 1.4 angstrom, we noted a 200% enhancement in the exchange bias in Fe/MgO/FeO compared to that in Fe/FeO.