| Summary: | Twisted bilayer graphene (TBG) provides an example of a system in which the
interplay of interlayer interactions and superlattice structure impacts
electron transport in a variety of non-trivial ways and gives rise to a
plethora of interesting effects. Understanding the mechanisms of electron
scattering in TBG has, however, proven challenging, raising many questions
about the origins of resistivity in this system. Here we show that TBG exhibits
high-temperature magnetooscillations originating from the scattering of charge
carriers between TBG minivalleys. The amplitude of these oscillations reveals
that interminivalley scattering is strong, and its characteristic time scale is
comparable to that of its intraminivalley counterpart. Furthermore, by
exploring the temperature dependence of these oscillations, we estimate the
electron-electron collision rate in TBG and find that it exceeds that of
monolayer graphene. Our study demonstrates the consequences of the relatively
small size of the superlattice Brillouin zone and Fermi velocity reduction on
lateral transport in TBG.
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