Figure 3. Auto-oscillations as a function of the angle between the d.c. current and the bias field.

(a) Sketch of the sample and measurement configuration. The bias field H is oriented at an angle φ with the d.c. current I_dc in the Pt. The precession of the YIG magnetization induces voltages V_x in the antenna and V_y across Pt, which are amplified and monitored by spectrum analysers. (b–d) V_x and V_y at H=0.47 kOe for three different angles φ in the 4-μm disc. (e) Dependence of the normalized signals in both circuits and (f), of the threshold current for auto-oscillations on φ. In e,f dashed lines show the expected angular dependences and error bars are estimated from the limited signal-to-background contrast of the inductive signals.