Resolution-dependent mechanisms for bimodal switching-time distributions   in simulated Fe nanopillars
  We study the magnetization-switching statistics following reversal of the applied field for three separate computational models representing the same physical system, an iron nanopillar. The primary difference between the models is the resolution of the computational lattice and, consequently, the intrinsic parameters that must be rescaled to retain similarity to the physical system. Considering the first-passage time to zero for the magnetization component in the longitudinal (easy-axis) direction, we look for applied fields that result in bimodal distributions of this time for each system and compare the results to the experimental system. We observe that the relevant fluctuations leading to bimodal distributions are different for each lattice resolution and result in magnetization-switching behavior that is unique to each computational model. Correct model resolution is thus essential for obtaining reliable numerical results for the system dynamics. 
S.H. Thompson, G. Brown, A. Kuhnle, P.A. Rikvold, M.A. Novotny