• 文献标题:   Intercalated rare-earth metals under graphene on SiC
  • 文献类型:   Article
  • 作  者:   ANDERSON NA, HUPALO M, KEAVNEY D, TRINGIDES M, VAKNIN D
  • 作者关键词:   rare earth, eu, dy, gd, intercalation, xmcd, graphene
  • 出版物名称:   JOURNAL OF MAGNETISM MAGNETIC MATERIALS
  • ISSN:   0304-8853 EI 1873-4766
  • 通讯作者地址:   Iowa State Univ
  • 被引频次:   3
  • DOI:   10.1016/j.jmmm.2018.11.007
  • 出版年:   2019

▎ 摘  要

Intercalation of rare earth metals (RE = Eu, Dy, and Gd) is achieved by depositing the RE metal on graphene that is grown on silicon-carbide (SiC) and by subsequent annealing at high temperatures to promote intercalation. STM images of the films reveal that the graphene layer is defect free and that each of the intercalated metals has a distinct nucleation pattern. Intercalated Eu forms nano-clusters that are situated on the vertices of a Moire pattern, while Dy and Gd form randomly distributed nano-clusters. X-ray magnetic circular dichroism (XMCD) measurements of intercalated films reveal the magnetic properties of these REs nano-clusters. Furthermore, field dependence and temperature dependence of the magnetic moments extracted from the XMCD show paramagnetic-like behaviors with moments that are generally smaller than those predicted by the Brillouin function. XMCD measurements of RE-oxides compared with those of the intercalated REs under graphene after exposure to air for months indicate that the graphene membranes protect these intercalants against oxidation.