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When hexagonal boron nitride (hBN) and graphene are aligned at zero or small twist angle, a moire structure is formed due to the small lattice constant mismatch between the two structures. In this work, we analyze magnetic ordering tendencies, driven by onsite Coulomb interactions, of encapsulated bilayer graphene (BG) forming a moire structure with one (hBN-BG) or both hBN layers (hBN-BG-hBN), using the random phase approximation. The calculations are performed in a fully atomistic Hubbard model that takes into account all $pi$-electrons of the carbon atoms in one moire unit cell. We analyze the charge neutral case and find that the dominant magnetic ordering instability is uniformly antiferromagnetic. Furthermore, at low temperatures, the critical Hubbard interaction $U_c$ required to induce magnetic order is slightly larger in those systems where the moire structure has caused a band gap opening in the non-interacting picture, although the difference is less than 6%. Mean-field calculations are employed to estimate how such an interaction-induced magnetic order may change the observable single-particle gap sizes.
Moire superlattices (MSL) formed in angle-aligned bilayers of van der Waals materials have become a promising platform to realize novel two-dimensional electronic states. Angle-aligned trilayer structures can form two sets of MSLs which could potenti
The effect of an hexagonal boron nitride (hBN) layer close aligned with twisted bilayer graphene (TBG) is studied. At sufficiently low angles between twisted bilayer graphene and hBN, $theta_{hBN} lesssim 2^circ$, the graphene electronic structure is
Van der Waals heterostructures employing graphene and hexagonal boron nitride (hBN) crystals have emerged as a promising platform for plasmonics thanks to the tunability of their collective modes with carrier density and record values for plasmonics
The Coulomb interaction is widely known to enhance the effective mass of interacting particles and therefore tends to favor a localized state at commensurate filling. Here, we will show that, in contrast to this consensus, in a van der Waals heterost
Interference of double moire patterns of graphene (G) encapsulated by hexagonal boron nitride (BN) can alter the electronic structure features near the primary/secondary Dirac points and the electron-hole symmetry introduced by a single G/BN moire pa