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An investigation of spin waves interacting with antiferromagnetic spin textures is meaningful for future spintronic and magnonic-based memory and logic applications. In this work, we numerically study the skyrmion dynamics driven by circularly polarized spin waves in antiferromagnets and propose a method of suppressing the Hall motion. It is demonstrated that the application of two circularly polarized spin waves with opposite chirality allows the skyrmion motion straightly along the intersection line of the two spin wave sources. The skyrmion speed depending on these parameters of the spin waves and system is estimated, and a comparison with other methods is provided. Furthermore, two depinning behaviors of the skyrmion related to the strengths of the defect are also observed in the simulations. Thus, the proposed method could be used in precisely modulating the skyrmion dynamics, contributing to skyrmion-based memory device design.

Searching for new methods to enhance the stability of antiferromagnetic (AFM) skyrmion during its motion is an important issue for AFM spintronic devices. Herein, the spin‐polarized current‐induced dynamics of a distorted AFM skyrmion is numerically studied, based on the Landau–Lifshitz–Gilbert simulations of the model with an anisotropic Dzyaloshinskii–Moriya (DM) interaction. It is demonstrated that the DM interaction anisotropy induces the skyrmion deformation, which suppresses the distortion during the motion and enhances the stability of the skyrmion. Moreover, the effect of the DM interaction anisotropy on the skyrmion velocity is investigated in detail, and the simulated results are further explained by Thiele's theory. This work unveils a promising strategy to enhance the stability and the maximum velocity of AFM skyrmion, benefiting future spintronic applications. [ABSTRACT FROM AUTHOR]

Herein, we investigate the behavior of skyrmions within a racetrack design incorporating voltage-controlled magnetic anisotropy (VCMA) gates. Our analysis encompassed multiple forces, including spin currents and anisotropy gradients induced by bias voltages. As a result, the efficient control of skyrmion dynamics was achieved across various VCMA gate configurations. Building upon these findings, we propose an efficient approach to reconfigurable skyrmion logic (RSL) in a thin antiferromagnetic (AFM) film through a versatile design. Our RSL harnesses the selective integration of VCMA, spin-polarized currents, and skyrmion-skyrmion (sky-sky) interactions to implement multiple logic gates, including AND, OR, XOR, NOT, NAND, XNOR, and NOR. The design brings a significant advantage with its simplified fabrication process, making the implementation of the RSL practical and accessible for various applications. Furthermore, the RSL enables seamless dynamic switching between logic gates, thereby enhancing its multifunctionality. Additionally, the strategic incorporation of sky-sky interactions and skyrmion-edge repulsion prominently facilitates the realization of complex gates, such as NAND, XNOR, and NOR gates, that typically require intricate design efforts. Hence, this streamlined integration of RSL, coupled with its adaptability to changing computational needs, underscores its potential as a practical solution for implementing high-functionality skyrmion-based logic gates.

We perform a stability analysis of an isolated atomic-sized antiferromagnetic skyrmion (AFM-Sk), formed on the superior layer of a magnetic bilayer. The coupling between both square lattices acts as an effective staggered magnetic field that stabilizes the AFM-Sk and reduces its radius. A suitable anisotropy constant of the bottom layer material keeps it close to the homogeneous AFM state. We compare the energy of the AFM-Sk with the energy of the AFM ground state. In addition, an estimation of the energy barrier that protects the skyrmion from being destabilized is provided and its value determined to be in the order of ∼ 300 K. The remarkable reduction in the skyrmion radius towards atomic size and avoiding an external magnetic field are key points in order to increase our ability to manipulate AFM-Sk on skyrmionic devices. Our calculations provide an insight into novel ways to create and manipulate AFM-Sk at the atomic scale. [ABSTRACT FROM AUTHOR]

• We theoretically proposed a method to localize the antiferromagnetic skyrmions. • The stable pinning of the skyrmion for certain ranges of injected current is demonstrated. • A precise track-selecting of the antiferromagnetic skyrmions is proposed. Reliable detection of antiferromagnetic (AFM) structures remains an open issue in experiments, although these structures such as skyrmions are suggested to play an important role in future spintronic applications. In this work, we theoretically proposed an alternative method to localize the AFM skyrmions along the direction of driving force through tuning magnetic anisotropy barriers by linear lattice defect design. The dependence of the depinning current on the magnitude and width of the defects and temperature is numerically investigated by solving the Landau-Lifshitz-Gilbert equation and also derived based on the Thiele's theory. The stable pinning of the skyrmion for certain ranges of the injected current is clearly demonstrated, which suggests an effective way in localizing the skyrmion. Based on the calculated results, we propose a method of precise track-selecting of the AFM skyrmions, which are meaningful for future two- and three- dimensional AFM spintronic device design. [ABSTRACT FROM AUTHOR]