Temperature dependence of magnetic exchange stiffness in iron and nickel

This work demonstrates a new technique to derive the magnetic exchange stiffness, A, using a measurement of the Bloch-type 180° domain wall width. Because this method is static and free from external fields, it enables the derivation of A over almost the entire temperature range up to near the Curie temperature, T C, which is difficult for existing techniques. With this technique, the temperature dependence of A for iron and nickel was assessed. Furthermore, after a systematic comparison of existing scaling functions, a promising scaling of A was demonstrated.