Quantum Electronic Transport in Graphene Superlattice Systems
Ming-Hao Liu1*
1Department of Physics, National Cheng Kung University, Tainan, Taiwan
* Presenter:Ming-Hao Liu, email:minghao.liu@phys.ncku.edu.tw
Electrons in graphene behave like massless Dirac fermions due to the close analogy between its electronic structure that can be well described by the Dirac equation and the energy dispersion of photons in vacuum governed by the Planck-Einstein relation. When a spatially periodic potential that varies in a length scale much longer than the lattice constant of graphene is applied, its conic band structure is strongly modified, forming the so-called miniband structure in the resulting graphene superlattices. Depending on the origin of the underlying periodic potential, there are different types of graphene superlattices, each exhibiting more complicated transport behaviors than simple graphene. This talk gives an overview of our recent progress on quantum transport simulations for various types of graphene superlattices, including hBN/graphene moire superlattices [1,2], gate-controlled two-dimensional [3] and one-dimensional [4] superlattices, and twisted graphene layers [5,6]. Most of the reviewed works are in collaboration with experiments.
[1] S.-C. Chen et al., Communications Physics 3, 71 (2020).
[2] R. Kraft et al., Phys. Rev. Lett. 125, 217701 (2020)
[3] R. Huber et al., Nano Lett. 21, 8046 (2020)
[4] W.-H. Kang et al., Phys. Rev. B 102, 195432 (2020)
[5] P. Rickhaus et al., Science Advances 6, no. 11, eaay8409 (2020)
[6] A. Mrenca-Kolasinska et al., arXiv:2110.00907 (2021)

Keywords: Graphene, Superlattice, Quantum transport, Tight-binding model