Fig. 3. Characterization of the current-induced effective fields.

(A and B) First and second harmonic voltages for the longitudinal effective field. H_L is the applied longitudinal magnetic field along the current direction (x axis). (D and E) First and second harmonic voltages for the transverse effective field. H_T is the applied transverse magnetic field transverse to the current direction (y axis). (C and F) Plots of the longitudinal and transverse field as a function of the peak current. The solid lines represent the linear fitting result with zero intercept. The red circles (blue squares) are data points for the M_z > 0 (M_z < 0). In the bilayer device, applying a current of 1 mA corresponds to a current density of 1.85 × 10¹⁰ A/m² in the Pt layer.