Effect of Spin Transfer Torque on Antiferromagnetic Film: Computer Simulations

The article aims to study the effect of polarized electric current on the magnetization in antiferromagnetic film by computer modeling. Research uses the Ising model, Monte Carlo method, and Metropolis algorithm. The model considers a two-layer film made of a non-magnetic conductor and a conductive antiferromagnetic film. Spin-polarized electric current is supplied through the lower boundary of the nonmagnetic film. The system simulates a sandwich system of ferromagnetic and antiferromagnetic films separated by a non-magnetic spacer. The role of ferromagnetic film is reduced to the polarization of electric current. Simulations have been carried out for different temperatures. The computer simulation examines the dependence of the magnetization in the antiferromagnetic film on the current strength and the polarization of the electron stream. A computer experiment showed the presence of a current threshold for an antiferromagnetic film well below the Neel temperature. The threshold value depends on the temperature and polarization of the electron stream. In the antiferromagnetic phase, there is a maximum magnetization that can be achieved with spin transfer torque. The current threshold and magnetization limit disappear when approaching the Neel temperature.