Correlation Between Dopant Atom Evaporation Field and Measured Site Preference in Atom Probe Tomography

Kasper A. Hunnestad; Constantinos Hatzoglou; Frida H. Danmo; Zewu Yan; Edith Bourret; Francois Vurpillot; Antonius T. J. van Helvoort; Sverre Selbach; Dennis Meier

arXiv · 2609.34008

Correlation Between Dopant Atom Evaporation Field and Measured Site Preference in Atom Probe Tomography

Kasper A. Hunnestad·Constantinos Hatzoglou·Frida H. Danmo·Zewu Yan·Edith Bourret·Francois Vurpillot·Antonius T. J. van Helvoort·Sverre Selbach·Dennis Meier

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Abstract

Complex oxides possess a wide range of electric, magnetic, and optical properties that can be precisely tuned by chemical doping. The atomic-scale analysis of the property-controlling dopants, however, becomes increasingly difficult towards low doping levels. Atom probe tomography (APT) offers chemical sensitivity and spatial resolution to image individual dopant atoms down to a few parts per million. To reliably extract such information, detailed knowledge about the atom-specific field evaporation processes is required. Here we demonstrate a first insight into the APT-measured atomic position of dopant atoms and the field evaporation conditions, using Zr-doped ErMnO3 as a model system. Our analysis reveals a substantial preferential retention of both matrix and dopant atoms which strongly affects the dopant site determination and can lead to an incorrect interpretation. The retention effect is determined by intrinsic and extrinsic parameters, such as the dopant's evaporation field and concentration and the analysis temperature, respectively, as we explain based on field-evaporation simulations. Our results are important for the APT-based analysis of individual dopant atoms in solid systems and the understanding of field evaporation dynamics at the atomic level in general.

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Kasper A. Hunnestad, Constantinos Hatzoglou, Frida H. Danmo, Zewu Yan, Edith Bourret, Francois Vurpillot, Antonius T. J. van Helvoort, Sverre Selbach, Dennis Meier. 2026-09-27. Correlation Between Dopant Atom Evaporation Field and Measured Site Preference in Atom Probe Tomography. https://arxiv.org/abs/2609.34008

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