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Comparison of two methods for describing the strain profiles in quantum dots

C. Pryor·J. Kim·L. W. Wang·A. J. Williamson·A. Zunger
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Abstract

The electronic structure of interfaces between lattice-mismatched semiconductor is sensitive to the strain. We compare two approaches for calculating such inhomogeneous strain -- continuum elasticity (CE, treated as a finite difference problem) and atomistic elasticity (AE). While for small strain the two methods must agree, for the large strains that exist between lattice-mismatched III-V semiconductors (e.g. 7% for InAs/GaAs outside the linearity regime of CE) there are discrepancies. We compare the strain profile obtained by both approaches (including the approximation of the correct C_2 symmetry by the C_4 symmetry in the CE method), when applied to C_2-symmetric InAs pyramidal dots capped by GaAs.

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C. Pryor, J. Kim, L. W. Wang, A. J. Williamson, A. Zunger. 1997-11-13. Comparison of two methods for describing the strain profiles in quantum dots. https://doi.org/10.1063/1.366631

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