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arXiv · 2310.18175

Effect of interfacial Dzyaloshinskii-Moriya interaction in spin dynamics of an Antiferromagnet coupled Ferromagnetic double-barrier Magnetic Tunnel Junction

Abstract

In this work, we have studied the spin dynamics of a synthethic Antiferromagnet (SAFM)$|$Heavy Metal (HM)$|$Ferromagnet (FM) double barrier magnetic tunnel junction (MTJ) in presence of Ruderman-Kittel-Kasuya-Yoside interaction (RKKYI), interfacial Dzyaloshinskii-Moriya interaction (iDMI), Néel field and Spin-Orbit Coupling (SOC) with different Spin Transfer Torque (STT). We employ Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation to investigate the AFM dynamics of the proposed system. We found that the system exhibits a transition from regular to damped oscillations with the increase in strength of STT for systems with weaker iDMI than RKKYI while display sustained oscillatons for system having same order of iDMI and RKKYI. On the other hand the iDMI dominating system exhibits self-similar but aperiodic patterns in absence of Néel field. In the presence of Néel field, the RKKYI dominating systems exhibit chaotic oscillations for low STT but display sustained oscillation under moderate STT. Our results suggest that the decay time of oscillations can be controlled via SOC. The system can works as an oscillator for low SOC but display nonlinear characteristics with the rise in SOC for systems having weaker iDMI than RKKYI while an opposite characteristic are noticed for iDMI dominating systems. We found periodic oscillations under low external magnetic field in RKKYI dominating systems while moderate field are necessary for sustained oscillation in iDMI dominating systems. Moreover, the system exhibits saddle-node bifurcation and chaos under moderate Néel field and SOC with suitable iDMI and RKKYI. In addition, our results indicate that the magnon lifetime can be enhanced by increasing the strength of iDMI for both optical and acoustic modes.

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BibTeXRIS

Reeta Devi, Nimisha Dutta, Arindam Boruah, Saumen Acharjee. 2023-10-27. Effect of interfacial Dzyaloshinskii-Moriya interaction in spin dynamics of an Antiferromagnet coupled Ferromagnetic double-barrier Magnetic Tunnel Junction. https://arxiv.org/abs/2310.18175

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