Fig. 3: Seebeck coefficient of the symmetry-broken ground states in the THF model.
From: Interplay between light and heavy electron bands in magic-angle twisted bilayer graphene
a, Illustration of the coexisting electronic species in the THF mapping of MATBG. The c electrons (red) are itinerant and weakly interacting, while the f electrons (blue) are highly localized in the moiré scale and incoherent due to strong electronic interactions. b–d, THF band structures for the KIVC symmetry-broken correlated ground states around ν = 0 (b), 0.8 (c) and 2 (d). The colour coding of the bands indicates their light or heavy character. The band structure in c is shown away from ν = 1 to highlight the spectrally broadened f states. e, Seebeck coefficient for the KIVC state in b at ν = 0. f, Seebeck coefficient for the KIVC + valley-polarized (VP) state in c in the vicinity of v = 1. g, Seebeck coefficient for the KIVC state in d in the vicinity of v = 2. At positive, non-zero integer fillings, the hole bands are formed by incoherent f electron excitations and give rise to a sign-preserving, oscillating Seebeck coefficient. The Seebeck coefficients in e–g are computed for T ≈ 0.65Torder.
