Numerical studies of demagnetizing effects in triangular ring arrays

We study the effect of the magnetostatic field in a two-dimensional periodic square array of Permalloy triangular rings by means of micromagnetic simulations. The rings have a lateral size of 50 nm, an edge width of 8 nm and the thickness is 10 nm. Applying an external field to one of the elements and assuming the rest of the array to be in the remanent state, we show how the remanent magnetization and coercive field are affected by the magnetostatic field of the array, both as a function of the distance between the elements and as a function of the number of elements used to model the periodic array. We provide an estimate of the minimum distance for an independent behavior of the elements, and we show that a model with the first and second nearest neighbors of an element can accurately approximate the effect of a much larger array