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Mott states proximitized to a relativistic electron gas in epitaxial graphene

Chitran Ghosal1, Siheon Ryee2,*, Zamin Mamiyev1, Maria-Elisabeth Federl5, Niklas Witt2,3,4, Tim Wehling2,3, and Christoph Tegenkamp1,†

  • *Contact author: sryee@physnet.uni-hamburg.de
  • †Contact author: christoph.tegenkamp@physik.tu-chemnitz.de
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Phys. Rev. B 111, 235426 – Published 12 June, 2025

DOI: https://doi.org/10.1103/vk9s-zzcw

Abstract

Graphene, renowned for its exceptional electronic and optical properties as a robust two-dimensional (2D) material, traditionally lacks electronic correlation effects. Proximity coupling offers a promising method to endow quantum materials with novel properties. In this study, we realized a 2D heterostructure by intercalating Sn into zero layer graphene on SiC(0001), allowing us to explore the coupling between a correlated 2D electron gas and a Dirac metal. This results in the stabilization of Sn-3 superlattice structures at the interface, which reveal Mott-Hubbard bands, in qualitative agreement with both experimental observations and theoretical predictions.

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Phys. Rev. B 111, 235426– Published 12 June, 2025
  • Received 6 December 2024
  • Revised 25 May 2025
  • Accepted 28 May 2025
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