Strong correlations, orbital magnetism, and superconductivity in multi-moiré twisted trilayer graphene

In twisted trilayer graphene (TTG), introducing two distinct twist angles, θ₁₂ and θ₂₃, to the top two layers and bottom two layers, respectively, typically generates two incommensurate moiré patterns. This approach significantly expands the parameter space for exploring novel phenomena. Theoretical calculations indicate the emergence of flat bands at specific twist angle combinations, defining two “magic lines” in the two-dimensional parameter θ₁₂ and θ₂₃ space. Previously studied TTG systems, including magic-angle twisted trilayer graphene, moiré quasicrystal (θ₁₂ = 1.4°, θ₂₃ = -1.9°), and magic-angle helical trilayer graphene are all positioned on the magic lines. In this talk, I will present our systematic experimental investigation of multiple new TTG systems along the magic lines. Transport measurements revealed strong correlations in all studied magic line TTG devices, while orbital magnetism and superconductivity emerging in a subset. Our findings establish multi-moiré graphene as a versatile platform for exploring and engineering strong correlations and topological properties.