Fast and universal approach for quantitative measurements of bistable hysteretic systems

Accurate and fast characterization of hysteretic systems can accelerate progress in fields as diverse as biomedicine, sensors, data storage, and logic devices. Here, we introduce a fast approach to determine magnetic parameters (intrinsic coercivities of elementary domains, interaction fields between the domains, and the variances of both) of bistable hysteretic systems. The approach uses the first few points in first-order reversal curves (FORC) to mathematically and empirically determine the projections of traditional FORC diagrams onto the reversal field and applied field axes. Since this projection approach only requires a few points per each reversal curve (rather than 100+ points for 100+ curves compared to the traditional FORC method), the time of measurement is reduced by 50-100x over traditional FORC measurements. In addition, the projection results do not contain the typical FORC artifacts that have been disputed for decades. As a proof of concept, the projection analysis was used to determine the magnetic parameters of several arrays of bistable magnetic nanowires (MNWs), and the results were compared with the hysteresis loop and FORC results. For non-interacting arrays of MNWs, all three methods give the intrinsic coercivity with minor difference. While, the differences become significant for the interacting arrays of the MNWs that will be discussed in details.