Approaches to evaluate thermal reversal of interacting magnetic grains

Summary form only given. In the authors´ analysis of thermal dynamic reversal of interacting magnetic grains, damping and thermal fluctuations are added to each independent normal mode. The micro-Hamiltonian basis of their model is the Heisenberg-Langevin approach to host oscillation modes interacting with a reservoir composed of many oscillators. The collective reversal of the magnetization is studied based upon the optimal reversal mode of the weakly thermally agitated system, which is obtained by minimization of the action functional of the system. They present results for perpendicular thin film media.