Anhysteretic and biased first magnetization curves for Finemet-type toroidal samples

The anhysteretic and a set of biased first magnetization (BFMC) curves together with a set of first-order reversal curves (FORC) were measured and modeled by the hyperbolic T(x) model for a Finemet-type nanocrystalline toroidal sample with a round hysteresis loop. Similar to the FORC diagram, a “fingerprint”-like distribution has been obtained from a set of BFMC curves using the mixed second-derivate method of Pike. It is concluded that while the FORC diagram gives the distribution of coercive fields (or Preisach distribution), the BFMC diagram gives the distribution of the critical field where the domain wall magnetization become unstable and split up.