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arXiv · 2408.11972

Efficient nanoscale imaging of solid-state phase transitions by transmission electron microscopy demonstrated on vanadium dioxide nanoparticles

Michal Horák·Peter Kepič·Jiří Kabát·Martin Hájek·Filip Ligmajer·Andrea Konečná·Tomáš Šikola·Vlastimil Křápek
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Abstract

We present annular dark field scanning transmission electron microscopy (ADF-STEM) as an efficient, fast, and non-destructive nanoscale tool for monitoring solid-state phase transition. Using metal-insulator transition in vanadium dioxide nanoparticles as an example, we characterize lattice and electronic signatures of the phase transition using analytical transmission electron microscopy including diffraction and electron energy-loss spectroscopy. We demonstrate that ADF-STEM shows a clear contrast across the transition, interpreted with the help of convergent electron beam diffraction as stemming from the crystal-lattice modification accompanying the transition. In addition, ADF-STEM utilizes 3--6 orders of magnitude lower electron dose when compared to electron microscopy techniques able to reveal the phase transition with the same spatial resolution and universality. The benefits of ADF-STEM are emphasized by recording a full hysteresis loop for the metal-insulator transition of a single vanadium dioxide nanoparticle. Our study opens the prospect for fast, non-destructive, large-area and nanoscale characterization of solid-state phase transitions.

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Michal Horák, Peter Kepič, Jiří Kabát, Martin Hájek, Filip Ligmajer, Andrea Konečná, Tomáš Šikola, Vlastimil Křápek. 2024-08-21. Efficient nanoscale imaging of solid-state phase transitions by transmission electron microscopy demonstrated on vanadium dioxide nanoparticles. https://arxiv.org/abs/2408.11972

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