Spin-dependent $\pi$$\pi^{\ast}$ gap in graphene on a magnetic substrate

• Main Authors: Sheverdyaeva, P. M, Bihlmayer, G, Cappelluti, E, Pacilé, D, Mazzola, F, Atodiresei, N, Jugovac, M, Grimaldi, I, Contini, G, Kundu, A. K, Vobornik, I, Fujii, J, Moras, P, Carbone, C, Ferrari, L
• Format: Journal Article
• Language: English
• Published: 27-04-2024
• Subjects: Physics - Mesoscale and Nanoscale Physics; Physics - Other Condensed Matter
• DOI: 10.48550/arxiv.2404.17887

Phys. Rev. Lett. 132, 266401 (2024) We present a detailed analysis of the electronic properties of
graphene/Eu/Ni(111). By using angle and spin-resolved photoemission
spectroscopy and ab initio calculations, we show that the Eu-intercalation of
graphene/Ni(111) restores the nearly freestanding dispersion of the
$\pi\pi^\ast$ Dirac cones at the K point with an additional lifting of the spin
degeneracy due to the mixing of graphene and Eu states. The interaction with
the magnetic substrate results in a large spin-dependent gap in the Dirac cones
with a topological nature characterized by a large Berry curvature, and a
spin-polarized van Hove singularity, whose closeness to the Fermi level gives
rise to a polaronic band.