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arXiv · 2409.10628

Single-atom-resolved vibrational spectroscopy of a dislocation

Hailing Jiang·Tao Wang·Zhenyu Zhang·Ruochen Shi·Xifan Xu·Bowen Sheng·Fang Liu·Weikun Ge·Ping Wang·Bo Shen·Peng Gao·Lucas R Lindsay·Xinqiang Wang
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Abstract

Phonon resistance from dislocation scattering is often divided into short-range core interactions and long-range strain field interactions. Using electron energy-loss spectroscopy on a GaN dislocation, we report observations of vibrational modes localized at specific core atoms (short-range) and strain-driven phonon energy shifts around the dislocation (long-range). Ab initio calculations support these findings and draw out additional details. This study reveals atomically resolved vibrational spectra of dislocations, thus offering insights for engineering improved material functionalities.

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Hailing Jiang, Tao Wang, Zhenyu Zhang, Ruochen Shi, Xifan Xu, Bowen Sheng, Fang Liu, Weikun Ge, Ping Wang, Bo Shen, Peng Gao, Lucas R Lindsay, Xinqiang Wang. 2024-09-16. Single-atom-resolved vibrational spectroscopy of a dislocation. https://arxiv.org/abs/2409.10628

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