Fig. 4: Stabilizing effect of electronic crystal by interlocking of the charge modulations in coupled graphene-insulator heterostructures.
From: Synergistic correlated states and nontrivial topology in coupled graphene-insulator heterostructures
Charge density modulations n(r) in real space after minimizing interlayer Coulomb interactions for a gapped Dirac state in graphene, and b electronic-crystal state in the substrate, which forms triangular superlattice. The blue stars annotate a maximum and a minimum of density in each state. The dashed lines connect two stars located at the same in-plane coordinate. c Condensation energy (per electron) of the electronic crystal state Econd vs. the carrier density n in the substrate. The green line represents the condensation energy of the decoupled system using the quantum Monte Carlo data, and the orange lines shows that of the coupled bilayer system, which is significantly stabilized by interlayer Coulomb coupling. The critical rs for Wigner-crystal transitions are also indicated in the coupled and decoupled cases, respectively.
