Generalized Peierls substitution for the tight-binding model of twisted multilayer graphene in a magnetic field
Title: Generalized Peierls substitution for the tight-binding model of twisted multilayer graphene in a magnetic field
Time: 15:10-16:10, Monday, 2022/05/02
The link for the online seminar :
Webex
https://nationaltaiwanuniversity-zbh.my.webex.com/nationaltaiwanuniversity-zbh.my/j.php?MTID=m5ae4f208954079a0154c908c5c3d7251
Abstract:
This work aims at addressing an important advanced methodology for twisted multilayer graphene (TMLG) in the presence of applied magnetic field, which is the Bloch-basis tight-binding model (TBM) in conjunction with the generalized Peierls substitution. We investigate extensively the band structures, Landau levels (LLs), and quantum Hall conductivity (QHC) of twisted bilayer graphene and twisted double bilayer graphene, as well as their dependence on the twist angle. Comparison between these crucial properties of monolayer graphene, Bernal bilayer graphene, and the twisted systems is carefully made to highlight the roles played by twisting. The unique selection rules of inter-LL transition, which is crucial for achieving a deep understanding of the step structures of QHC, are identified through the properties of LL wave functions. Remarkably, for the first time, the effective TBM is combined with the generalized Peierls substitution to investigate the magnetic quantization of twisted bilayer graphene at magic angle. Our theoretical model opens up an opportunity for comprehension of the interplay between an applied magnetic field and the twisting effect associated with multilayer graphene. The proposed method is expected to be extendable for the calculation of magnetic quantization problems of other complex systems.
