Magnetic domain state diagnosis using hysteresis reversal curves

We present results for a series of hysteresis measurements that provide information about remanent, induced, transient-free, and transient magnetization components. These measurements, and differences between measurement types, enable production of six types of first-order reversal curve (FORC)-like diagrams which only double the number of measurements involved in a conventional FORC measurement. These diagrams can be used to distinguish magnetic signatures associated with each domain state. When analyzing samples with complex magnetic mineral mixtures, the contrasting domain state signatures are mixed together in a traditional FORC diagram, but these signatures can be identified individually when using the various FORC diagrams discussed here. The ability to make different FORC measurements and to identify separately each magnetic component by investigating different magnetization types can provide much-improved understanding of the information provided by FORC diagrams. In particular, the transient hysteresis FORC diagram provides a method to measure the nucleation field of magnetic vortices and domain walls. We provide a simple explanation for FORC results from natural multidomain samples that are not explained by conventional domain wall pinning models. We also provide software for processing the different types of FORC data.