Exponential dependence between motion acceleration and diameters of skyrmions under the driven of periodical strains

The internal strain in practical materials is usually seen as defects and a large of methods have been proposed to avoid its appearance. However, strains in magnetic materials can be effective in regulating the performance mediated by magnetoelastic coupling effect. Herein, we theoretically demonstrate the motion of skyrmions driven by time-dependent periodical strains which imitate strain fluctuations in real materials. It is found that the motion acceleration of skyrmions is exponential correlation with diameters and skyrmions can be rebounded near the end of magnetic racetrack for larger size of diameters. Such a motion results from the excitation of spin wave modes on the position of circular domain walls in skyrmions. Our results can provide insight for manipulating skyrmions by strain engineering for applications in information storage and processing.