Abstract
Graphene oxide (GO) membranes have been widely explored for their excellent physical and chemical properties, and abundant functional groups. In this work, we report the improvement of the perpendicular magnetic anisotropy (PMA) of CoFeB thin films by applying a coating of GO membranes. We observe that the PMA of the CoFeB/MgAl–O stacks is strongly enhanced by the coating of GO membranes and even reaches 0.6 mJ m−2 at room temperature after an annealing process. The critical thickness of the membrane-coated CoFeB for switching the magnetization from the out-of-plane to the in-plane axis exceeds 1.6 nm. First-principle calculations are performed to investigate the contribution of the GO membranes to the magnetic anisotropy energy (MAE). Due to changes in the hybridization of 3d orbitals, varying the location of the C atomic layer with Co changes the contribution of the Co–C stacks to PMA. Thus, the large PMA achieved with GO membranes can be attributed to the orbital hybridization of the C and O atoms with the Co orbitals. These results provide a comprehensive understanding of the PMA and point towards opportunities to achieve multifunctional graphene-composite spintronic devices.
Original language | English (US) |
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Pages (from-to) | 52938-52944 |
Number of pages | 7 |
Journal | RSC Advances |
Volume | 7 |
Issue number | 83 |
DOIs | |
State | Published - 2017 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: This work was supported by National Natural Science Foundation(51501098, 61574083, 61434001), National Key R&D Program (2016YFA0200400), National Basic Research Program (2015CB352101), Special Fund for Agroscientific Research in the Public Interest (201303107) of China, Research Fund from Beijing Innovation Center for Future Chip, and Beijing Natural Science Foundation (No. 4164087). The authors are also thankful for the support of the Independent Research Program (2014Z01006) of Tsinghua University, in part by funding from King Abdullah University of Science and Technology (KAUST). J. F. acknowledges Youth Innovation Promotion Association of Chinese Academy of Sciences (No. 2017010). We would like to thank Dr Caihua Wan for discussions.