The remagnetization process feature of trilayer nanodisks

The remagnetization process and the distribution of magnetic moments in arrays of trilayer nanodisks Co(10 nm)/Pd(0.8 nm)/Co(10 nm) with diameters D = 200 and 400 nm were studied by the magnetooptical Kerr effect (MOKE) and magnetic force microscopy (MFM). It is shown that in the nanodisks with D = 200 nm the magnetisation reversal process can be carried out by the vortex states or one-domain configurations with the antiparallel orientation of moments in the adjacent ferromagnetic layers. In arrays of nanodisks with D = 400 nm the vortex states are formed only.