Mott states proximitized to a relativistic electron gas in epitaxial graphene

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-<a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msqrt><a:mn>3</a:mn></a:msqrt></a:math> superlattice structures at the interface, which reveal Mott-Hubbard bands, in qualitative agreement with both experimental observations and theoretical predictions.