Fractal quantum transport of a 2D electron gas in a superlattice

Aitor Garcia-Ruiz^1*, Ming-Hao Liu¹

¹Physics, National Cheng Kung university, Tainan city, Taiwan

* Presenter:Aitor Garcia-Ruiz, email:aitor.garcia-ruiz@phys.ncku.edu.tw

We study the band structure and quantum transport of a two-dimensional (2D) electron gas affected by a nanometer-scale periodic potential under magnetic fields. Using the continuum model, we compute the band structure of the system with and without magnetic fields, which reveals the formation of a self-similar fractal band gaps for values of the magnetic field of about ~1T. Additionally, we simulate the quantum transport across a realistic two-terminal device affected by the same potential and find a remarkably good agreement between its conductance and the position of the bands. Our results could be tested on a wide range of 2D semiconductors, like transition metal dichalcogenides, where the edge of the conduction band is approximately parabolic.

Keywords: Transition metal dichalcogenides, superlattice, Hofstadter's butterfly, Quantum transport