@article{KrivenkovGoliasMarchenkoetal.2017,
  author    = {Krivenkov, Maxim and Golias, Evangelos and Marchenko, Dmitry and Sanchez-Barriga, Jaime and Bihlmayer, Gustav and Rader, Oliver and Varykhalov, Andrei},
  title     = {Nanostructural origin of giant Rashba effect in intercalated graphene},
  series = {2D Materials},
  volume    = {4},
  journal   = {2D Materials},
  number    = {3},
  publisher = {IOP Publ. Ltd.},
  address   = {Bristol},
  issn      = {2053-1583},
  doi       = {10.1088/2053-1583/aa7ad8},
  pages     = {11},
  year      = {2017},
  abstract  = {To enhance the spin-orbit interaction in graphene by a proximity effect without compromising the quasi-free-standing dispersion of the Dirac cones means balancing the opposing demands for strong and weak graphene-substrate interaction. So far, only the intercalation of Au under graphene/Ni(111) has proven successful, which was unexpected since graphene prefers a large separation (similar to 3.3 angstrom) from a Au monolayer in equilibrium. Here, we investigate this system and find the solution in a nanoscale effect. We reveal that the Au largely intercalates as nanoclusters. Our density functional theory calculations show that the graphene is periodically stapled to the Ni substrate, and this attraction presses graphene and Au nanoclusters together. This, in turn, causes a Rashba effect of the giant magnitude observed in experiment. Our findings show that nanopatterning of the substrate can be efficiently used for engineering of spin-orbit effects in graphene.},
  language  = {en}
}
@article{KrivenkovMarchenkoSanchezBarrigaetal.2021,
  author    = {Krivenkov, Maxim and Marchenko, Dimitry and S{\´a}nchez-Barriga, Jaime and Golias, Evangelos and Rader, Oliver and Varykhalov, Andrei},
  title     = {Origin of the band gap in Bi-intercalated graphene on Ir(111)},
  series = {2D Materials},
  volume    = {8},
  journal   = {2D Materials},
  number    = {3},
  publisher = {IOP Publ. Ltd.},
  address   = {Bristol},
  issn      = {2053-1583},
  doi       = {10.1088/2053-1583/abd1e4},
  pages     = {15},
  year      = {2021},
  abstract  = {Proximity to heavy sp-elements is considered promising for reaching a band gap in graphene that could host quantum spin Hall states. The recent report of an induced spin-orbit gap of 0.2 eV in Pb-intercalated graphene detectable by spin-resolved photoemission has spurred renewed interest in such systems (Klimovskikh et al 2017 ACS Nano 11, 368). In the case of Bi intercalation an even larger band gap of 0.4 eV has been observed but was assigned to the influence of a dislocation network (Warmuth et al 2016 Phys. Rev. B 93, 165 437). Here, we study Bi intercalation under graphene on Ir(111) and report a nearly ideal graphene dispersion without band replicas and no indication of hybridization with the substrate. The band gap is small (0.19 eV) and can be tuned by +/- 25 meV through the Bi coverage. The Bi atomic density is higher than in the recent report. By spin-resolved photoemission we exclude induced spin-orbit interaction as origin of the gap. Quantitative agreement of a photoemission intensity analysis with the measured band gap suggests sublattice symmetry breaking as one of the possible band gap opening mechanisms. We test several Bi structures by density functional theory. Our results indicate the possibility that Bi intercalates in the phase of bismuthene forming a graphene-bismuthene van der Waals heterostructure.},
  language  = {en}
}