Twist-angle transferable continuum model and second flat Chern band in twisted MoTe2 and WSe2

Year: 2025

Type: article

Abstract: We develop a twist-angle transferable continuum model for twisted transition metal dichalcogenide (tTMD) homobilayers, using tMoTe 2 and tWSe 2 as examples. All model parameters are extracted from density functional theory (DFT) calculations at a single twist angle (3.89°) and monolayer data. Our model captures both lattice relaxation effects and the long-range behavior of piezoelectric and ferroelectric potentials. Leveraging lattice relaxations obtained via machine learning force fields (MLFFs), the model can be efficiently transferred to other twist angles without requiring additional DFT calculations. It accurately reproduces the DFT band dispersions and quantum geometries across a wide range of twist angles. Furthermore, our model reveals that a second flat Chern band arises near 2° when the interlayer potential difference becomes comparable to the interlayer tunneling. This continuum model provides a clear understanding and starting point for engineering novel electronic phases in moiré TMDs through twist angles and lattice relaxations.

Source: npj Quantum Materials

DOI: 10.1038/s41535-025-00828-6

Authors: Xiao-Wei Zhang, Kaijie Yang, Chong Wang, Xiaoyu Liu, Ting Cao, Di Xiao

Institutions: University of Washington, Pacific Northwest National Laboratory

Language: English

Topic: 2D Materials and Applications

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,890

Funders: National Science Foundation, U.S. Department of Energy, University of Washington, National Energy Research Scientific Computing Center, Office of Science, Division of Materials Research, Basic Energy Sciences, Pacific Northwest National Laboratory

OpenAlex ID: W4416918593