On the zero-field quantization of the anomalous quantum Hall effect in moiré 2D layers

Abstract

In recent breakthrough experiments, twisted moiré layers of transition metal dichalcogenides are found to manifest both integer (IQAHE) and fractional (FQAHE) quantum anomalous Hall effects in zero applied magnetic field because of the underlying flat band topology and spontaneous breaking of the time reversal invariance. In the current work, we critically analyze the experimental values of the quantized conductance in each case to emphasize the role of disorder in the problem, pointing out that obtaining accurate quantized conductance in future experiments would necessitate better contacts and lower disorder.

arXiv commentUpdated version (including added Fig. 8) to appear in Phys. Rev. B (Letter)

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Cited by in corpus (4)

• Variational Mapping of Chern Bands to Landau Levels: Application to Fractional Chern Insulators in Twisted MoTe${}_2$
• Electronic transport, metal-insulator transition, and Wigner crystallization in transition metal dichalcogenide monolayers
• Integer and fractional quantum anomalous Hall effects in pentalayer graphene
• Time-dependent conserved operators for autonomous systems and quantization of resistance