Fig. 2: Local and nonlocal resistance in TDBG device with twist angle 1.18° at 1.5 K.
From: Bulk valley transport and Berry curvature spreading at the edge of flat bands
a, b Local and nonlocal resistance as a function of charge density and electric field. The dashed overlay line shows the location of line slices plotted in c–e. nS denotes the charge density to fill one moiré flat band. Insets show the micrographs of the device with voltage (current) terminals indicated by red (blue) dots. The scale bar corresponds to 5 μm. c–e Both local and nonlocal resistance, along with the calculated ohmic contribution, around moiré gaps at n = −nS (c), and n = nS (e) for the zero electric field and around the CNP gap at n = 0 (d) for a nonzero electric field. The nonlocal resistance is much larger than the ohmic contribution at the gaps. The inset in c zooms the resistance variation around n = −nS/2 at D/ϵ0 = 0 V nm−1, where nonlocal resistance is almost zero in spite of significant local resistance.
