High frequency ferromagnetic resonance measurements in magnetic fluids

Abstract Measurement of the frequency and field-dependent, complex susceptibility, χ ( ω , H ) of magnetic fluids is a proven method for investigating the resonant and dynamic properties of magnetic fluids. Here we demonstrate how, parameters, such as the anisotropy constant, K , the precessional decay time, τ o , and the gyromagnetic constant, γ , can be obtained by plotting data obtained at constant frequency and variable field in a Cole–Cole format and then fitting the Cole–Cole plots to the equations of Landau and Lifshitz.