Synchronization of spin-torque driven nanooscillators for point contacts on a quasi-1D nanowire: Micromagnetic simulations

Abstract

In this paper we present detailed numerical simulation studies on the synchronization of two spin-torque nanooscillators (STNO) in the quasi-1D geometry: magnetization oscillations are induced in a thin NiFe nanostripe by a spin polarized current injected via square-shaped CoFe nanomagnets on the top of this stripe. In a sufficiently large out-of-plane field, a propagating oscillation mode appears in such a system. Due to the absence of the geometrically caused wave decay in 1D systems, this mode is expected to enable a long-distance synchronization between STNOs. Indeed, our simulations predict that synchronization of two STNOs on a nanowire is possible up to the intercontact distance 3 mkm (for the nanowire width 50 nm). However, we have also found several qualitatively new features of the synchronization behaviour for this system, which make the achievement of a stable synchronization in this geometry to a highly non-trivial task. In particular, there exist a minimal distance between the nanocontacts, below which a synchronization of STNOs can not be achieved. Further, when the current value in the first contact is kept constant, the amplitude of synchronized oscillations depends non-monotonously on the current value in the second contact. Finally, for one and the same currents values through the contacts there might exist several synchronized states (with different frequencies), depending on the initial conditions.

13 pages with 4 figurews, recently submitted to PRB

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• Spin Transfer Torques
• Bias-driven large power microwave emission from MgO-based tunnel magnetoresistance devices
• Large-amplitude coherent spin waves exited by spin-polarized current in nanoscale spin valves
• Phase locking dynamics of dipolarly coupled vortex-based spin transfer oscillators
• Experimental Test of Analytic Theory of Spin Torque Oscillator Dynamics
• Spin-torque shot noise in magnetic tunnel junctions
• Scalable design of tailored soft pulses for coherent control

Cited by in corpus (5)

• Robust synchronization of an arbitrary number of spin-torque driven vortex nanooscillators
• Optimizing magneto-dipolar interactions for synchronizing vortex based spin-torque nano-oscillators
• Synchronization of spin-transfer torque oscillators by spin pumping, inverse spin Hall, and spin Hall effects
• Controlling the synchronization properties of two dipolarly coupled vortex based spin-torque nano-oscillators by the intermediate of a third one
• Voltage Controlled Magnetic Anisotropy Based Low Energy Switching of a Ferromagnet on a Topological Insulator