Thickness and magnetic-field dependence of domain switching in isolated and interacting permalloy contacts

Control of the magnetic behavior of microstructured ferromagnets is a crucial prerequisite for magnetoelectronic and spintronic devices. Microstructured permalloy (Ni83Fe17) contacts of various thicknesses on the same sample are studied experimentally by means of magnetic-force microscopy at remanence and in external magnetic fields. The results are compared to micromagnetic simulations. Switching fields and corresponding magnetization patterns of the contacts are determined by measuring and simulating entire hysteresis curves. From the simulated magnetization data magnetic-force-microscopy images are calculated, which allow straight-forward comparison. Magnetostatic interaction is probed using contacts located in close vicinity. The domain switching in these contacts occurs at magnetic fields one order of magnitude smaller than in isolated ones.