Interaction-driven giant thermopower in magic-angle twisted bilayer graphene

  title={Interaction-driven giant thermopower in magic-angle twisted bilayer graphene},
  author={Arup Kumar Paul and Ayana Ghosh and Souvik Chakraborty and Ujjal Kanti Roy and Rani Dutta and K. Watanabe and T. Taniguchi and Animesh Panda and Adhip Agarwala and Subroto Mukerjee and Sumilan Banerjee and Anindya Sundar Das},
  journal={Nature Physics},
Thermopower, a non-invasive probe, is a sensitive tool to study the electronic structure near the singular points of Fermi surface as its magnitude and sign depends on the asymmetry of the density of states at the Fermi energy. Here, we report thermopower measurements in magic-angle twisted bilayer graphene (MtBLG) as function of carrier density, temperature and magnetic field using sensitive Johnson noise thermometry. At low temperatures (<10K) thermopower or Seebeck coefficient (S) exhibits… 
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