A model of an isolated column of metal evaporated tape

Metal Evaporated (ME) tape comprises bundles of inclined columns each of which consists of small crystalline gains. To simulate the magnetic behaviour of ME tape we have developed a model, using a Monte Carlo algorithm to represent a single column of spherical grains whose radii are generated from a log-normal distribution. The dynamic process of the magnetic moments is explored by utilizing the Landau-Lifschitz equations. We demonstrate that the microstructure of the column and direction of the easy axes influence the magnetic reversal process. By varying the strength of the exchange coupling parameter its effect on the amount of co-operative switching is reported. The results suggest that high exchange coupling acts to keep moments aligned, resulting in higher values of coercivity. The reversal mechanism is initiated at the ends of the column and then propagates through the column.