Room temperature skyrmions in an exchange biased antiferromagnet

Kumari Gaurav Rana (1) , Rafael Lopes Seeger (1) , Sandra Ruiz-Gómez (2) , Roméo Juge (1) , Qiang Zhang (1) , Van Tuong Pham (1) , Mohamed Belmeguenai (3) , Stéphane Auffret (1) , Michael Foerster (2) , Lucia Aballe (2) , Gilles Gaudin (1) , Vincent Baltz (1) , Olivier Boulle (1)

1 SPINTEC - SPINtronique et TEchnologie des Composants
2 ALBA Synchrotron light source [Barcelone]
3 LSPM - Laboratoire des Sciences des Procédés et des Matériaux

Magnetic skyrmions are topological spin textures holding great potential as nanoscale information carriers. Recently, skyrmions have been predicted in antiferromagnets, with key advantages in terms of stability, size and dynamical properties over their ferromagnetic analogs. However, their experimental demonstration is lacking. Here we show that skyrmions can be stabilized at zero field and room temperature at the interface of sputtered IrMn thin films exchange-coupled to a ferromagnetic layer. This was realised by replicating the skyrmionic spin texture of the ferromagnet in the antiferromagnet, via annealing above the blocking temperature of the ferromagnet/antiferromagnet bilayer. Using the high-spatial-resolution magnetic microscopy technique XMCD-PEEM, we observe the skyrmions within the IrMn interfacial layer from the XMCD signal of the uncompensated Mn spins at the interface. This result opens up a path for logic and memory devices based on skyrmion manipulation in antiferromagnets.

Domaines: Matière Condensée [cond-mat]

Kumari Gaurav Rana, Rafael Lopes Seeger, Sandra Ruiz-Gómez, Roméo Juge, Qiang Zhang, et al.. Room temperature skyrmions in an exchange biased antiferromagnet. 2021. ⟨hal-02984059v1⟩