近日，中国科学院理论物理研究所李伟团队研究了扭曲MoTe₂中分数陈绝缘子与量子反常霍尔晶体。该项研究成果发表在2026年1月13日出版的《科学通报》杂志上。

近期实验研究在零磁场条件下，于扭曲二碲化钼体系中发现分数陈绝缘体态。如何在真实模型中理解相互作用对拓扑物相的影响，已成为重要的理论挑战。

研究组针对扭曲二碲化钼体系构建了莫尔超晶格模型，并采用先进的张量网络方法进行系统探究。基态计算揭示了丰富多样的相互作用驱动且依赖于填充数的拓扑物相，包括分数陈绝缘体、陈绝缘体以及广义维格纳晶体等已被实验观测到的物态。针对分数陈绝缘体态，动力学模拟展示了具有有限电荷间隙的单粒子激发连续谱，反映了分数化电荷激发的特征。

有限温度计算进一步确定了其特征电荷激活温度与铁磁转变温度，从而解释了现有实验间的差异。此外，基于这一真实晶格模型，研究组预言了在分数填充下可出现具有整数霍尔电导的量子反常霍尔晶体。通过整合基态、有限温度及动力学分析，该研究为理解扭曲二碲化钼及相关莫尔体系中的关联拓扑物相建立了一个系统框架。

附：英文原文

Title: Fractional Chern insulator and quantum anomalous Hall crystal in twisted MoTe2

Author: Xiaoyu Wang c, Wei Li a

Issue&Volume: 2026/01/13

Abstract: Recent experimental advances have uncovered fractional Chern insulator (FCI) states in twisted MoTe2 (tMoTe2) systems under zero magnetic field. Understanding the interaction effects on topological phases within realistic model presents a significant theoretical challenge. Here, we construct a moiré superlattice model tailored for tMoTe2 and conduct investigations using state-of-the-art tensor-network methods. Our ground-state calculations reveal a rich variety of interaction-driven and filling-dependent topological phases, including FCIs, Chern insulators, and generalized Wigner crystals, which are revealed in recent experiments. For FCI state, dynamical simulations uncover a single-particle excitation continuum with a finite charge gap, reflecting the fractionalized charge excitations. Finite-temperature calculations further determine characteristic charge activation and ferromagnetic transition temperatures, reconciling existing experimental discrepancies. Furthermore, using this realistic lattice model, we predict the presence of quantum anomalous Hall crystals exhibiting integer Hall conductivity at fractional fillings in tMoTe2. By integrating ground-state, finite-temperature, and dynamical analyses, our work establishes a comprehensive framework for understanding correlated topological phases in tMoTe2 and related moiré systems.

DOI: 10.1016/j.scib.2026.01.014

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927326000150