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Atomic scale lattice distortions and domain wall profiles

K. H. Ahn·T. Lookman·A. Saxena·A. R. Bishop
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Abstract

We present an atomic scale theory of lattice distortions using strain related variables and their constraint equations. Our approach connects constrained {\it atomic length} scale variations to {\it continuum} elasticity and describes elasticity at several length scales. We apply the approach to a two-dimensional square lattice with a monatomic basis, and find the elastic deformations and hierarchical atomic relaxations in the vicinity of a domain wall between two different homogeneous strain states. We clarify the microscopic origin of gradient terms, some of which are included phenomenologically in Ginzburg-Landau theory, by showing that they are anisotropic.

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K. H. Ahn, T. Lookman, A. Saxena, A. R. Bishop. 2003-09-02. Atomic scale lattice distortions and domain wall profiles. https://doi.org/10.1103/physrevb.68.092101

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