Temperature dependence of the macroscopic ferri–ferromagnetic transition in amorphous Y–Co/Gd–Co bilayers

We studied the temperature dependence of the macroscopic ferri–ferromagnetic transition in amorphous Y–Co/Gd–Co bilayers. The samples were produced by sputtering, and characterized by vibrating sample magnetometer and transverse magneto-optical Kerr effect at low temperature. From a model of the unusual shaped domain wall (DW) at the interface of the bilayer, we determined the temperature dependence of the thickness δ and relative position Δ of the DW and, also the exchange constant A.