Electrical Nonlinearity in Vortex‐Type Tunneling Magnetoresistance Sensors

Abstract Vortex‐type tunneling magnetoresistance (TMR) sensors have garnered significant attention due to their hysteresis‐free characteristics. However, the quantitative relationship between magnetization and magnetoresistance (MR) remains elusive owing to the non‐uniform magnetization distribution, with the nonlinear effects lacking rigorous interpretation. Herein, a parallel‐discretized magnetic tunnel junctions model (PD‐MTJs model) for vortex‐type TMR sensors is proposed based on micromagnetic simulations and Slonczewski's theory. This framework successfully establishes a deterministic magnetization‐MR correlation, demonstrating good agreement with experimental data. Furthermore, a localized growth modification strategy for the reference layer (RL) is proposed based on this model, achieving a theoretical linearity below 0.15% within a ±10 mT operational range. These findings provide critical insights into magnetization‐MR coupling mechanisms and advance the design of hysteresis‐free spintronic sensors.