Final Published Version
Physical Review Materials
Antiferromagnetically (AFM) coupled skyrmions offer potential advantages for spintronic devices, including reduced dipolar fields that may enable smaller skyrmion sizes and a reduction of the skyrmion Hall effect. However, the topological stability of AFM-coupled skyrmions subjected to dramatic spin deformation through low-temperature cycling has not been investigated. Here we report the discovery of a topological spin memory effect for AFM-coupled skyrmion pairs in [Co/Gd/Pt]10 multilayered films. Photoemission electron microscopy imaging shows that bubble skyrmions in the multilayer that are stable at room temperature evolve into complex in-plane spin textures as the temperature is lowered and reform completely when the sample is warmed back up. Simulations demonstrate that Dzyaloshinskii-Moriya interactions play a key role in this spin memory effect, and furthermore reveal that the topological charge is preserved throughout the dramatic spin texture rearrangement and recovery. These results highlight a key aspect of topological protection—the preservation of the topological properties under continuous deformation—and also provide a promising avenue for information encryption and recovery.
Wang, X., Stuart, A. R., Swyt, M. S., Quispe Flores, C. M., Clark, A. T., Fiagbenu, A., Chopdekar, R. V., Lapa, P. N., Xiao, Z., Keavney, D., Rosenberg, R., Vogel, M., Pearson, J. E., te Velthuis, S. G. E., Hoffmann, A., Buchanan, K. S. and X. M. Cheng. 2022. “Topological spin memory of antiferromagnetically coupled skyrmion pairs in Co/Gd/Pt multilayers.” Phys. Rev. Materials 6: 084412.