Abelian and non-Abelian fractionalized states in twisted MoTe$_2$: A generalized Landau-level theory

Abstract

Fractional Chern insulators are lattice analogs of fractional quantum Hall states that realize fractionalized quasiparticles without an external magnetic field. A key strategy to understand and design these phases is to map Chern bands onto Landau levels (LLs). Here, we introduce a universal framework that variationally decomposes Bloch bands into generalized LLs, providing a controlled and quantitative characterization of their effective LL nature. Applying this approach to twisted bilayer MoTe$_2$ modeled by first-principles-derived moiré Hamiltonians, we find that the first moiré valence band is dominated by the generalized zeroth LL across a broad range of twist angles, facilitating the formation of Abelian fractional Chern insulators in the Jain sequences. The second moiré band, renormalized via Hartree-Fock calculations at hole filling $ν_h = 2$, is dominated by the generalized first LL at twist angles $θ= 2.45^\circ$ and $2.13^\circ$. At $θ= 2.45^\circ$, we find numerical evidence for a non-Abelian Moore--Read (MR) state at $ν_h = 5/2$, with consistent signatures in both the energy spectrum and the particle entanglement spectrum. Interpolation studies further demonstrate an adiabatic connection between this state and the MR state in the conventional first LL. In contrast, at $θ= 2.13^\circ$, a charge-density-wave state prevails in the competition with the MR state due to the larger bandwidth. Our variational mapping provides a theoretical framework for exploring exotic fractionalized phases, including non-Abelian states, in realistic systems.