The role of damping rate amplitude in the synchronization of two coupled oscillators

Abstract

We investigate the synchronization phenomenon between two Spin-transfer Torque Nano-Oscillators (STNOs) of different frequencies in two pillar systems under vortex configuration detunings or driving frequencies. The oscillators' mutual synchronization occurs through magnetic dipolar interaction. Our micromagnetic simulations show that an amplitude fluctuation referred to as ${\Gamma }_p$ has a significant impact on determining the synchronization frequency. The evolution of frequency and amplitude fluctuation rate in two different oscillator sizes versus external perpendicular field are compared and discussed. Our results reveal that the oscillator with lower ${\Gamma }_p$, referred to as the "Leader" oscillator, leads the synchronization process. As such, the "follower" oscillator adjusts its frequency as to that of the "Leader", thus achieving synchronization. We believe that taking ${\Gamma }_p$ into consideration can help in controlling synchronization frequencies in future building blocks of any network multi-array spintronics' devices.

References in corpus (8)

• The design and verification of Mumax3
• Spin torque building blocks
• Vowel recognition with four coupled spin-torque nano-oscillators
• Synchronization of spin-transfer oscillators driven by stimulated microwave currents
• Mutual synchronization of spin torque nano-oscillators through a non-local and tunable electrical coupling
• Phase locking dynamics of dipolarly coupled vortex-based spin transfer oscillators
• Perfect and robust phase-locking of a spin transfer vortex nano-oscillator to an external microwave source
• Selective control of vortex polarities by microwave field in two robustly synchronized spin-torque nano-oscillators