Electronic Signatures of the Multiple Moiré Components in the Two-Dimensional CrCl₃/Au Heterostructure Observed by Scanning Tunneling Microscopy and Spectroscopy.

Abstract

Moiré patterns are a central motif in van der Waals heterostructures arising from the superposition of two-dimensional (2D) incommensurate lattices. These patterns reveal a wealth of correlated effects, influencing electronic, magnetic, and structural phenomena. While diffraction techniques typically resolve multiple moiré wave vectors corresponding to the incommensurate nature of the underlying lattices, Scanning Tunneling Microscopy (STM) often reveals only a dominant superperiod. In this work, we address this apparent discrepancy through an STM study of a twisted monolayer of CrCl₃ on Au(111). We observe the coexistence of several Fourier components of moiré patterns at a fixed twist angle, whose relative intensity depends on the tunneling bias. Fourier analysis of STM data uncovers hidden higher-order moiré components not visible in STM topographic images, while spectroscopy maps reveal that the spectral weight of each pattern varies with electron energy. Our results establish that STM selectively probes in the same area distinct quasiperiodic modulations depending on electronic confinement, providing a unified framework that reconciles real-space and reciprocal-space observations of complex moiré superstructures.