Figure 5. Electrical synchronization of two spin torque oscillators connected directly in series.
(a) Electrical circuit for the synchronization of two nano-oscillators connected in series with a single DC current source. The two oscillators are connected by a gold wire bonding and the length of cable between the two oscillators is of a few mm. (b) Power spectral density of the two nano-oscillators depending on the applied DC current at Hperp=200 kA m−A. (The sample diameter is 300 nm).