Extension of the magic-angle system in twisted bilayer-graphene by adjusting parameter values
DOI:
https://doi.org/10.47611/jsrhs.v12i1.4361Keywords:
Quantum, Graphene, Twisted, Bilayer, Hopping, Materials, SimulationAbstract
Twisted-bilayer graphene (TBG) has attracted significant attention in the world of condensed matter physics in the past few years owing to its unique properties. Consisting of two sheets of graphene, when TBG is rotated by a certain magic angle, it can transition into a remarkable superconducting state. Using the low-energy continuum Hamiltonian model developed by Bistritzer and MacDonald, along with theory on the relationship between tunneling amplitudes and magic angle1, we change parameters of the model in order to analyze the effect such changes have on the band structure of the overall system. For any twist angle, inputting corresponding amplitude values yields far flatter bands than those yielded by inputting standard amplitude values. Specifically, those models with twist angle and amplitudes lower than those of the conventional model possess flatter bands than the absolute flattest bands hitherto observed.
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