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arXiv · 1106.2955

Epitaxial interfaces between crystallographically mismatched materials

Steven C. Erwin·Cunxu Gao·Claudia Roder·Jonas Lähnemann·Oliver Brandt
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Abstract

We report an unexpected mechanism by which an epitaxial interface can form between materials having strongly mismatched lattice constants. A simple model is proposed in which one material tilts out of the interface plane to create a coincidence-site lattice that balances two competing geometrical criteria---low residual strain and short coincidence-lattice period. We apply this model, along with complementary first-principles total-energy calculations, to the interface formed by molecular-beam epitaxy of cubic Fe on hexagonal GaN and find excellent agreement between theory and experiment.

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Steven C. Erwin, Cunxu Gao, Claudia Roder, Jonas Lähnemann, Oliver Brandt. 2011-06-15. Epitaxial interfaces between crystallographically mismatched materials. https://doi.org/10.1103/physrevlett.107.026102

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