Flat band and Lifshitz transition in long-range-ordered supergraphene obtained by Erbium intercalation

A. Zaarour (1) , V. Malesys (1) , J. Teyssandier (1) , M. Cranney (1) , E. Denys (1) , J L Bubendorff (2, 1) , A. Florentin (3, 1) , L. Josien (1) , F. Vonau (1) , D. Aubel (1) , A. Ouerghi (1) , C. Bena (4) , L. Simon (1)

1 IS2M - Institut de Science des Matériaux de Mulhouse
2 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
3 CHRU Nancy - Centre Hospitalier Régional Universitaire de Nancy
4 IPHT - Institut de Physique Théorique - UMR CNRS 3681

We report the observation of graphene doped up to the Lifshitz transition obtained solely by the intercalation of Erbium atoms. ARPES measurements show that a wide flat band is generated around the M point of the Brillouin zone. We propose that this is the effect of an induced spin-orbit coupling. Scanning Tunneling Microscopy (STM) experiments reveal a longrange ordered hexagonal superstructure: we argue that this reflects the ordering of the intercalated Er atoms acting as impurities. This system provides a playground to study the interaction between a magnetic order and a divergent density of states at the Fermi level.

Domains: Materials Science [cond-mat.mtrl-sci]

A. Zaarour, V. Malesys, J. Teyssandier, M. Cranney, E. Denys, et al.. Flat band and Lifshitz transition in long-range-ordered supergraphene obtained by Erbium intercalation. Physical Review Research, 2023, 5 (1), pp.013099. ⟨10.1103/PhysRevResearch.5.013099⟩. ⟨hal-04024130⟩