In section 6.4 we described a method for extracting the coercive field of the twodimensional antidot layers. The assumption with this approach is that the layers are independent, however different layers interact via the exchange coupling. A Monte Carlo simulation is used to simulate the reversal behaviour of a stack of exchangecoupled twodimensional layers. It is assumed that all magnetic moments in one twodimensional layer point in the same direction, i.e. each layer is treated as a single StonerWohlfarth particle (see figure 6.11).
By taking the computed coercive field from the twodimensional model as a function of , we can determine an effective anisotropy energy (arising from the adapted StonerWohlfarth model described in appendix B considering anisotropy and Zeeman components) for each StonerWohlfarth layer with holes of the size :
The layers are coupled by the exchange interaction and the exchange energy can be computed between two neighbouring layers and :

By performing a Monte Carlo simulation of the system of coupled
StonerWohlfarth layers using the equations above and input parameters
for
from the twodimensional simulations shown in
figure 6.12, we are able to more accurately
compute the coercive field with respect to the height of the film, and
therefore use the results of the twodimensional simulations to
understand a simplified model of the threedimensional system.