Micromagnetic Study on the Influence of Nanowire Width and Dzyaloshinskii-Moriya Interaction on Domain Wall Propagation in CoFeB Nanowires under Nanosecond Current Pulses Della Nurbaiti1, Maria Metantomwate2, Aysa sabrina1, Melenia Tambunan1, Ramlan1, Candra Kurniawan*3
Physics Department FMIPA University of Sriwijaya, Palembang, Indonesia1.
Physics Department FMIPA, IPB University2.
Research Center for Energy Materials, National Research and Innovation Agency (BRIN), Bld 440, KST BJ Habibie Tangerang Selatan 15314, Banten, Indonesia*3
Abstract
The rapid growth of data storage demand necessitates the development of advanced spintronic devices that surpass the limitations of conventional hard disk drives (HDDs) and solid-state drives (SSDs). Among the emerging technologies, Racetrack Memory has gained significant attention due to its potential for achieving ultrahigh density, non-volatility, and low energy consumption. This study investigates the micromagnetic behavior of domain wall (DW) propagation in CoFeB nanowires driven by nanosecond current pulse injection, emphasizing the influence of Dzyaloshinskii-Moriya Interaction (DMI). Micromagnetic simulations were carried out using the Object Oriented Micromagnetic Framework (OOMMF), employing the spin-transfer torque (STT) dynamic model, while the DMI term was incorporated through an extended OOMMF module. The simulation systematically varied nanowire widths, material parameters, and current pulse profiles to examine their effects on DW dynamics. Results indicate that reducing the nanowire width increases domain wall velocity up to an optimal limit, beyond which instability and velocity breakdown occur. The inclusion of DMI enhances DW stability by suppressing distortions during propagation, thereby maintaining a steady velocity even under high current densities. Additionally, nanosecond-scale current pulses are found to be effective in achieving controlled and repeatable domain wall displacement without thermal degradation. These findings provide a deeper understanding of DW motion mechanisms in CoFeB nanowires and underscore the critical role of DMI in improving performance reliability. The insights gained from this work contribute to the design of high-speed, energy-efficient, and scalable racetrack memory architectures for next-generation spintronic data storage systems.
