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arXiv · 2302.01671

Moiré Fringes in Conductive Atomic Force Microscopy

L. Richarz·J. He·U. Ludacka·E. Bourret·Z. Yan·A. T. J. van Helvoort·D. Meier
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Abstract

Moiré physics plays an important role for the characterization of functional materials and the engineering of physical properties in general, ranging from strain-driven transport phenomena to superconductivity. Here, we report the observation of moiré fringes in conductive atomic force microscopy (cAFM) scans gained on the model ferroelectric Er(Mn,Ti)O$_3$. By performing a systematic study of the impact of key experimental parameters on the emergent moiré fringes, such as scan angle and pixel density, we demonstrate that the observed fringes arise due to a superposition of the applied raster scanning and sample-intrinsic properties, classifying the measured modulation in conductance as a scanning moiré effect. Our findings are important for the investigation of local transport phenomena in moiré engineered materials by cAFM, providing a general guideline for distinguishing extrinsic from intrinsic moiré effects. Furthermore, the experiments provide a possible pathway for enhancing the sensitivity, pushing the resolution limit of local transport measurements by probing conductance variations at the spatial resolution limit via more long-ranged moiré patterns.

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L. Richarz, J. He, U. Ludacka, E. Bourret, Z. Yan, A. T. J. van Helvoort, D. Meier. 2023-02-03. Moiré Fringes in Conductive Atomic Force Microscopy. https://doi.org/10.1063/5.0145173

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