The Effect of the Interface Width on the Exchange Interaction Constant between Ferro- and Antiferromagnets

Abstract—In the approximation of the average spin method, a system of equations for determining the average magnetic moments of atoms at the interface between a ferromagnet and an antiferromagnet is formulated. It is possible to simulate the dependences of interfacial exchange interaction constant A_in on the temperature, antiferromagnetic layer thickness, and interface width by solving the system of equations for an ultrathin Ni/NiO film. It is found that the interfacial exchange interaction constant in a film with a fixed interface width at low temperatures increases with an increase in the thickness of the antiferromagnetic layer. With an increase in the interface width, the A_in value decreases by a factor of 1.3 and reaches its minimum level.