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arXiv · 1908.07297

Structure of amorphous Cu$_2$GeTe$_3$ and a model for its fast phase-change mechanism

Jens R. Stellhorn·Benedict Paulus·Shinya Hosokawa·Wolf-Christian Pilgrim·Nathalie Boudet·Nils Blanc·Yuji Sutou
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Abstract

The structure of amorphous Cu$_2$GeTe$_3$ is investigated by a combination of anomalous x-ray scattering and extended x-ray absorption fine structure experiments. The experimental data are analyzed with a reverse Monte Carlo modeling procedure, and interpreted in terms of the short- and intermediate-range order. Based on this information, a model for the phase transition in Cu$_2$GeTe$_3$ is proposed, in which atoms move toward the center of the 6-fold rings of the crystal structure, leading to the formation of wrong bonds and a broader distribution of ring structures, but also preserving some structural motifs of the crystal.

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Jens R. Stellhorn, Benedict Paulus, Shinya Hosokawa, Wolf-Christian Pilgrim, Nathalie Boudet, Nils Blanc, Yuji Sutou. 2019-08-20. Structure of amorphous Cu$_2$GeTe$_3$ and a model for its fast phase-change mechanism. https://arxiv.org/abs/1908.07297

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