Magnetization Reversal Time for Ferromagnetic and Antiferromagnetic Chains in the Heisenberg Model

A new analytical method for the study of the magnetic properties of finite-length monatomic and biatomic chains with uniaxial magnetic anisotropy in the framework of the Heisenberg model is described. The method allows the calculation of the reversal time of the magnetization of ferromagnetic and antiferromagnetic chains. Three cases are considered: spontaneous remagnetization, remagnetization under the interaction with a scanning tunneling microscope, and remagnetization in an external magnetic field. The method gives results that are in good agreement with the results of kinetic Monte Carlo simulations. As examples, two physical systems are considered: biatomic Fe chains on a Cu
$_2$
N/Cu(001) surface and biatomic Co chains on a Pt(997) surface.