Magnetic reversal of double-layer patterned nanosquares

The magnetic reversal process of double-layer patterned nanosquares was studied by means of micromagnetic simulations. Different types of hysteresis loops were observed, depending on the thickness ratio of the two layers and the interlayer distance. Antiparallel state was induced by different mechanisms, either through the differential magnetostatic fields or through the differential coercitivies of the two layers. It is revealed that the interlayer magnetostatic interaction is the key factor that determines the reversal behavior. In this study, we constructed a diagram for the dependence of the types of hysteresis loops on thickness ratios and interlayer distances. The switching dynamics for the double-layer patterned nanosquares were also investigated. (C) 2005 American Institute of Physics.