Dynamic calculation of the responsivity of monodomain fluxgate magnetometers

A model is presented describing the dynamic response of a single-domain fluxgate magnetometer over a wide range of operating conditions in terms of a single measurement of a hysteresis loop or the permeability of the fluxgate's ferromagnetic core. The model is based on the Landau-Lifshitz-Gilbert equation, which describes the dynamics of a coherently rotating ferromagnet. Measurements of the response of a permalloy thin-film fluxgate and a molybdenum-permalloy tube fluxgate demonstrate the accuracy and limitations of the model.