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arXiv · 1206.4105

Melt-growth dynamics in CdTe crystals

X. W. Zhou·D. K. Ward·B. M. Wong·F. P. Doty
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Abstract

We use a new, quantum-mechanics-based bond-order potential (BOP) to reveal melt-growth dynamics and fine-scale defect formation mechanisms in CdTe crystals. Previous molecular dynamics simulations of semiconductors have shown qualitatively incorrect behavior due to the lack of an interatomic potential capable of predicting both crystalline growth and property trends of many transitional structures encountered during the melt $\rightarrow$ crystal transformation. Here we demonstrate successful molecular dynamics simulations of melt-growth in CdTe using a BOP that significantly improves over other potentials on property trends of different phases. Our simulations result in a detailed understanding of defect formation during the melt-growth process. Equally important, we show that the new BOP enables defect formation mechanisms to be studied at a scale level comparable to empirical molecular dynamics simulation methods with a fidelity level approaching quantum-mechanical methods

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X. W. Zhou, D. K. Ward, B. M. Wong, F. P. Doty. 2012-06-19. Melt-growth dynamics in CdTe crystals. https://doi.org/10.1103/physrevlett.108.245503

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