Suzanne G. E. te Velthuis

Affiliation

• Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA

Title

Electrical creation and manipulation of magnetic skyrmion bubbles

Abstract

The ability to controllably create and move magnetic skyrmions is key to enabling the technological implementation of skyrmion-based spintronics. In this presentation, the electric generation and manipulation of skyrmions in a magnetic multilayer system at room-temperature will be discussed. Magnetostatically stabilized skyrmion structures, magnetic bubbles, can form in magnetic thin films with perpendicular magnetic anisotropy. By adding an additional layer with strong spin-orbit coupling to the ferromagnet, it is possible to generate an interfacial Dzyaloshinskii Moriya interaction, which stabilizes chiral magnetic domain walls around the bubble, resulting in a skyrmion spin structure. These skyrmion bubbles can then be electrically manipulated utilizing spin Hall effects. This is demonstrated for a Ta/CoFeB/TaOx trilayer, where skyrmions can be generated via diverging electric charge currents in a process that is similar to droplet formation in surface-tension driven fluid flow [1]. This provides a practical approach for skyrmion formation on demand. Experimentally we determined the electric current vs. magnetic field phase diagram for the skyrmion formation and we demonstrated the manipulation of the dynamically created skyrmions. The resultant motion of the skyrmion bubbles is characterized by stochastic depinning due to random pinning sites. We further reveal the manipulation and motion of these skyrmions by electric currents in a variety of devices. Work at Argonne was supported by the Department of Energy, Office of Science, Basic Energy Science, Materials Sciences and Engineering Division, while work at UCLA was supported by TANMS.

References

[1] W. Jiang, P. Upadhyaya, W. Zhang, G. Yu, M. B. Jungfleisch, F. Y. Fradin, J. E. Pearson, O. Heinonen, Y. Tserkovnyak, K. L. Wang, S. G. E. te Velthuis, and A. Hoffmann, Blowing magnetic skyrmion bubbles, Science 349, 283 (2015).