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arXiv · 2304.08405

Ferroelastic twin angles at the surface of CaTiO$_\mathrm{3}$ quantified by PhotoEmission Electron Microscopy

G. Magagnin·C. Lubin·M. Escher·N. Weber·L. Tortech·N. Barrett
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Abstract

We use photoemission electron microscopy to measure the ferroelastic twin wall angles at the surface of CaTiO$_\mathrm{3}$(001) and deduce the strain ordering. We analyze the angular dependence of the photoelectron emission from different domain surfaces, each with their own characteristic tilt angle in the factory roof-like topography. By considering the surface topography as a field perturbation, the offset in the photoemission threshold can be directly related to the tilt angles. With knowledge of the symmetry allowed twin walls we quantify twin topography between 179.1{\deg} to 180.8{\deg}.

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G. Magagnin, C. Lubin, M. Escher, N. Weber, L. Tortech, N. Barrett. 2023-04-17. Ferroelastic twin angles at the surface of CaTiO$_\mathrm{3}$ quantified by PhotoEmission Electron Microscopy. https://arxiv.org/abs/2304.08405

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