Synchronization of spin-transfer torque oscillators by spin pumping, inverse spin Hall, and spin Hall effects

TL;DR

This paper proposes a novel method to synchronize multiple spin-transfer torque oscillators using spin pumping, inverse spin Hall, and spin Hall effects, demonstrated through simulations of coupled nano-magnets with feedback loops.

Contribution

It introduces a new synchronization technique for spin-torque oscillators leveraging spin Hall effects and feedback, supported by simulation results.

Findings

Synchronization achieved via spin Hall and inverse spin Hall effects

Simulations show effective phase locking of nano-magnets

Feedback loop enhances oscillator coherence

Abstract

We have proposed a method to synchronize multiple spin-transfer torque oscillators based on spin pumping, inverse spin Hall, and spin Hall effects. The proposed oscillator system consists of a series of nano-magnets in junction with a normal metal with high spin-orbit coupling, and an accumulative feedback loop. We conduct simulations to demonstrate the effect of modulated charge currents in the normal metal due to spin pumping from each nano-magnet. We show that the interplay between the spin Hall effect and inverse spin Hall effect results in synchronization of the nano-magnets.