Measuring the Local Twist Angle and Layer Arrangement in Van der Waals Heterostructures

Abstract

The properties of Van der Waals heterostructures are determined by the twist angle and the interface between adjacent layers as well as their polytype and stacking. Here we describe the use of spectroscopic Low Energy Electron Microscopy (LEEM) and micro Low Energy Electron Diffraction (μLEED) methods to measure these properties locally. We present results on a MoS${}_2$/hBN heterostructure, but the methods are applicable to other materials. Diffraction spot analysis is used to assess the benefits of using hBN as a substrate. In addition, by making use of the broken rotational symmetry of the lattice, we determine the cleaving history of the MoS${}_2$ flake, i.e., which layer stems from where in the bulk.

References in corpus (9)

• Electric Field Effect in Atomically Thin Carbon Films
• Van der Waals heterostructures
• Magic-angle graphene superlattices: a new platform for unconventional superconductivity
• 2D materials and van der Waals heterostructures
• Microscopic thickness determination of thin graphite films formed on SiC from quantized oscillation in reflectivity of low-energy electrons
• Graphene field-effect transistors based on boron nitride gate dielectrics
• Magnetic gap opening in rhombohedral-stacked multilayer graphene from first principles
• Scattering resonances in graphene
• Thickness characterization of atomically-thin WSe${}_2$ on epitaxial graphene by low-energy electron reflectivity oscillations

Cited by in corpus (9)

• Direct Imaging and Electronic Structure Modulation of Moiré Superlattices at the 2D/3D Interface
• Imaging moiré deformation and dynamics in twisted bilayer graphene
• Observation of flat $\Gamma$ moiré bands in twisted bilayer WSe${}_2$
• Determining the Twist Angle of Bilayer Graphene by Machine Learning Analysis of its Raman Spectrum
• Non-universal Transverse Electron Mean Free Path through Few-layer Graphene
• Quantitative analysis of spectroscopic Low Energy Electron Microscopy data: High-dynamic range imaging, drift correction and cluster analysis
• Fano physics behind the N-resonance in graphene
• Unusual flat and extended morphology of intercalated Cu under MoS2
• Quantifying Twist Angles in Cuprate Heterostructures with Anisotropic Raman Signatures