Advanced Materials, Vol.16, No.23-24, 2155-2155, 2004
Ultrahigh-Density Arrays of ferromagnetic nanorings on macroscopic areas
Arrays of ten billion Co nanorings, with inner diameters of 100 nm, wall widths of 20 nm, and of an ultrahigh areal density of 45 rings mum(-2), are fabricated on a macroscopic area. Magnetometric measurements and micromagnetic simulations reveal two parallel switching processes: a vortex reversal process and a rotating onion process.