Bilayer Quantum Hall States in an n-type Wide Tellurium Quantum Well

TL;DR

This study demonstrates the fabrication and measurement of bilayer quantum Hall states in n-type wide tellurium quantum wells, revealing Landau level hybridization and topological properties in 2D materials.

Contribution

It introduces a method to realize and analyze bilayer quantum Hall states in tellurium quantum wells, advancing understanding of topological and Weyl physics in 2D systems.

Findings

Observation of profound Shubnikov-de Haas oscillations in both layers

Identification of Landau level hybridization between layers

Detection of bilayer quantum Hall states at specific filling factors

Abstract

Tellurium (Te) is a narrow bandgap semiconductor with a unique chiral crystal structure. The topological nature of electrons in the Te conduction band can be studied by realizing n-type doping using atomic layer deposition (ALD) technique on two-dimensional (2D) Te film. In this work, we fabricated and measured the double-gated n-type Te Hall-bar devices, which can operate as two separate or coupled electron layers controlled by the top gate and back gate. Profound Shubnikov-de Haas (SdH) oscillations are observed in both top and bottom electron layers. Landau level hybridization between two layers, compound and charge-transferable bilayer quantum Hall states at filling factor 4, 6, and 8 are analyzed. Our work opens the door for the study of Weyl physics in coupled bilayer systems of 2D materials.