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arXiv · 2404.17887

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

P. M. Sheverdyaeva·G. Bihlmayer·E. Cappelluti·D. Pacilé·F. Mazzola·N. Atodiresei·M. Jugovac·I. Grimaldi·G. Contini·A. K. Kundu·I. Vobornik·J. Fujii·P. Moras·C. Carbone·L. Ferrari
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Abstract

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.

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P. M. Sheverdyaeva, G. Bihlmayer, E. Cappelluti, D. Pacilé, F. Mazzola, N. Atodiresei, M. Jugovac, I. Grimaldi, G. Contini, A. K. Kundu, I. Vobornik, J. Fujii, P. Moras, C. Carbone, L. Ferrari. 2024-04-27. Spin-dependent $\pi$$\pi^{\ast}$ gap in graphene on a magnetic substrate. https://doi.org/10.1103/physrevlett.132.266401

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