Higher Landau-Level Analogues and Signatures of Non-Abelian States in Twisted Bilayer MoTe2
ORAL
Abstract
Recent experimental discovery of fractional Chern insulators at zero magnetic field in moire superlattices has sparked intense interests in bringing Landau level physics to flat Chern bands. In twisted MoTe2 bilayers (tMoTe2), recent theoretical and experimental studies have found three consecutive flat Chern bands at twist angle ~ 2 degrees. In this work, we investigate whether higher Landau level physics can be found in these consecutive Chern bands. At twist angles 2.00 degrees and 1.89 degrees, we identify four consecutive C = 1 bands for the K valley in tMoTe2. By constructing Wannier functions directly from density functional theory (DFT) calculations, a six-orbital model is developed to describe the consecutive Chern bands, with the orbitals forming a honeycomb lattice. Exact diagonalization on top of Hartree-Fock calculations are carried out with the Wannier functions. Especially, when the second moire miniband is half-filled, signatures of non-Abelian states are found. Our Wannier-based approach in modelling moire superlattices is faithful to DFT wave functions and can serve as benchmarks for continuum models. The possibility of realizing non-Abelian anyons at zero magnetic field also opens up a new pathway for fault-tolerant quantum information processing.
*The exact diagonalization study is supported by DOE Award No. DE-SC0012509. The density-functional theory calculation is supported by the Center on Programmable Quantum Materials, an Energy Frontier Research Center funded by DOE BES under award DE-SC0019443. The machine learning of moire structure is supported by the discovering AI@UW Initiative and by the National Science Foundation under Award DMR-2308979. This work uses Microsoft Azure credits funded by discovering AI@UW Initiative.
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Publication: arXiv: 2404.05697
Presenters
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Chong Wang
- University of Washington
- Tsinghua University