Anatomy of Dzyaloshinskii–Moriya interaction at interfaces: from Fert-Levy type DMI at Co/Pt to Rashba effect induced DMI at Co/graphene*

The antisymmetric exchange interaction, Dzyaloshnskii-Moriya Interaction (DMI), has gained an intense research effort due to its crucial role in the creation, annihilation and the influence on the dynamics of magnetic Skyrmions and chiral domain wall. Here, we will present a general DMI calculation approach based on DFT total energy calculations and show the calculated DMI at Co/Pt interfaces and the comparison with experiments. We will address the main features and microscopic mechanism of typical Fert-Levy type DMI at Co/Pt interface from first-principles by clearing up several fundamental questions: how does the DMI extend away from the interface? Where is the corresponding electronic energy source located? [1] How to design enhanced DMI systems? [2,3] Moreover, we will go beyond Fert-Levy type DMI systems to avoid using heavy metals but with simple ferromagnet/graphene interfaces. [4] At the end, we will give a perspective on the topic with new systems which may also give large DMI but are different to FM/HM and FM/graphene.
[1] HY, A. Thiaville, S. Rohart, A. Fert, M. Chshiev, Phys. Rev. Lett. 115, 267210 (2015)
[2] HY, O. Boulle, V. Cros, A. Fert, M. Chshiev, Scientific Reports 8, 12356(2018).
[3] O. Boulle, J. Vogel, HY, et al., Nature Nanotech. 11, 449 (2016).
[4] HY, G. Chen, et al., Nature Materials 17, 605(2018)