Engineering Correlated Dirac Fermions and Flat Bands on SiC with Transition-Metal Adatom Lattices
Abstract
We propose three transition-metal adatom systems on SiC surfaces as a versatile platform to realize massless Dirac fermions and flat bands with strong electronic correlations. Using density functional theory combined with the constrained random phase approximation and dynamical mean-field theory, we investigate the electronic properties of Ti, V, and Cr adatoms. The triangular surface lattices exhibit narrow bandwidths and effective two-band Hubbard models near the Fermi level, originating from partially filled adatom d orbitals. For the undoped systems our calculations reveal two distinct Mott insulating ground states. While the V lattice is a paramagnetic textbook case with large local moments, the Cr lattice, in contrast, is on the edge of a phase transition toward a flat-band Fermi liquid. The Ti lattice realizes a heavy Dirac semimetal at zero doping.
Fields of Study & Subjects
Graphene research and applications
Silicon Carbide Semiconductor Technologies
Superconductivity in MgB2 and Alloys
Publication details
- Journal / source
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Volume
- 136
- Issue
- 24
- Pages
- 246503–246503
- Publication date
- 30 April 2026
- Language
- EN