Magnetization dynamics modulated by Dzyaloshinskii-Moriya interaction in the double-interface spin transfer torque magnetic tunnel junction

TL;DR

This paper demonstrates that the detrimental effects of Dzyaloshinskii-Moriya interaction in double-interface spin transfer torque magnetic tunnel junctions can be nearly eliminated through the suppressing effect of RKKY interaction, enhancing device stability.

Contribution

It reveals that RKKY interaction can suppress DMI effects in double-interface STT-MTJs, a novel insight for improving magnetic tunnel junction performance.

Findings

DMI effects are significantly reduced in double-interface structures.

RKKY interaction suppresses DMI, improving thermal stability.

Theoretical and simulation analyses support the suppression mechanism.

Abstract

Currently double-interface MTJs have been developed for enhancing the thermal stability barrier in small technology node. Dzyaloshinskii-Moriya interaction (DMI) inevitably exists in such devices due to the use of the heavy-metal/ferromagnet structures. Previous studies have demonstrated the detrimental effect of DMI on the conventional single-interface spin transfer torque (STT) MTJs. Here in this work we will prove that the detrimental effect of the DMI could be almost eliminated in the double-interface STT-MTJ. This conclusion is attributed to the suppressing effect of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction on the DMI. Detailed mechanisms are analyzed based on the theoretical models and micromagnetic simulation results. Our work highlights the importance of appropriately controlling the DMI in two free layers of the double-interface STT-MTJ.