Self-oscillations of spins in a nanodimensional spin waveguide with localized sources of spin-polarized current

Spin oscillations and their phase synchronization are discovered in a spin 1D waveguide (nanowire) after the local injection of a spin-polarized current in the vertical (perpendicular) geometry of magnetization. The mode composition of nonlinear spin self-oscillations is analyzed for a single nano-oscillator using the effect of spin transfer torque with regard to spin wave runaway over the 1D waveguide and synchronized spin self-oscillations at current pumping by two nano-oscillators. It is shown specifically that, along with simple (“nontopological”) oscillation modes, in which singular points in the oscillation amplitude spatial distribution are absent, the 1D waveguide may support modes with pole-type singular points inside the current pumping domain, which are characteristic of the geometry of a precessing 2π-domain boundary. A diagram for frequency- and current-detuning-synchronized spin self-oscillations that are excited by two spin nano-oscillators in the 1D spin waveguide is constructed.