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A period-doubled structure for the 90-degree partial dislocation in silicon

J. Bennetto·R. W. Nunes·David Vanderbilt
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Abstract

We suggest that the commonly-accepted core structure of the 90-degree partial dislocation in Si may not be correct, and propose instead a period-doubled structure. We present LDA, tight-binding, and classical Keating-model calculations, all of which indicate that the period-doubled structure is lower in energy. The new structure displays a broken mirror symmetry in addition to the period doubling, leading to a wide variety of possible soliton-like defects and kinks.

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J. Bennetto, R. W. Nunes, David Vanderbilt. 1997-04-09. A period-doubled structure for the 90-degree partial dislocation in silicon. https://doi.org/10.1103/physrevlett.79.245

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