Fig. 2
Current-induced spin wave auto-oscillations. a Current dependent ST-FMR linewidth of the FMR (red circles) and localized (blue circles) modes for positive field (filled symbols) and negative field (open symbols). The error bars are calculated using the standard error of ΔH while fitting the ST-FMR signals to a function consists of symmetric and anti-symmetric Lorentzian function. b, c Electrical measurements of the power spectral densities of spin wave auto-oscillations vs. applied field measured under a direct current of (b) +2 mA and (c) −2 mA. Label I and II indicate low-field and high-field auto-oscillations, respectively. d–f, μ-BLS measurements of the frequency vs. applied field showing the intensity of the FMR and the localized mode measured at 0 mA (d), +1.2 mA (e), and −1.2 mA (f). g, h, show the change of the BLS counts as a function of current at μ0H = 0.2 T and μ0H = 0.7 T. Solid red lines in g, h, are a linear fitting, and fitting to the theoretical prediction of Eq. (84a) in ref. 29, respectively
