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DOE OSTI · 1631317

Microscopic model for the stacking-fault potential and the exciton wave function in GaAs

Durnev, Mikhail V.·Glazov, Mikhail M.·Linpeng, Xiayu·Viitaniemi, Maria L. K.·Matthews, Bethany·Spurgeon, Steven R.·Sushko, Peter V.·Wieck, Andreas D.·Ludwig, Arne·Fu, Kai-Mei C.
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Abstract

Two-dimensional stacking fault defects embedded in a bulk crystal can provide a homogeneous trapping potential for carriers and excitons. Here we utilize state-of-the-art structural imaging cou- pled with density functional and effective-mass theory to build a microscopic model of the stacking- fault exciton. The diamagnetic shift and exciton dipole moment at different magnetic fields are calculated and compared with the experimental photoluminescence of excitons bound to a single stacking fault in GaAs. The model is used to further provide insight into the properties of excitons bound to the double-well potential formed by stacking fault pairs. This microscopic exciton model can be used as an input into models which include exciton-exciton interactions to determine the excitonic phases accessible in this system.

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BibTeXRIS

Durnev, Mikhail V., Glazov, Mikhail M., Linpeng, Xiayu, Viitaniemi, Maria L. K., Matthews, Bethany, Spurgeon, Steven R., Sushko, Peter V., Wieck, Andreas D., Ludwig, Arne, Fu, Kai-Mei C.. 2020-03-20. Microscopic model for the stacking-fault potential and the exciton wave function in GaAs. https://doi.org/10.1103/physrevb.101.125420

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