Experimental studies on interlayer Coulomb interactions in graphene-based moiré structure

Near the satellite Dirac point (sDP) in graphene moiré structures, diverse physical phenomena originating from strong Coulomb interactions have been found in electron transport studies. Here, we present recent studies on the effect of interlayer Coulomb interaction in two different types of graphene-based moiré structures. First, in graphene-thin hBN-graphene moiré heterostructures, we compare drag resistances near the sDP and near the main Dirac point whose density and temperature dependence exhibit unique features from the moiré band. Second, by fabricating near-zero-angle-twisted double bilayer graphene, we show how the symmetry broken Landau levels in moiré band evolve under perpendicular electric field that tunes the layer symmetry. We will discuss the possible origins and implications of these findings in view of interlayer Coulomb interactions in the moiré systems.