This work analyzes excitonic fine structure and related optical anisotropies with atomistic many-body theory. It focuses on how realistic geometry, composition, and symmetry breaking determine the low-energy excitonic manifold.
Keywords: dark exciton
Main result: fine details of excitonic splitting and polarization are controlled by atomistic symmetry, realistic shape, and material inhomogeneity. Simplified continuum expectations are often insufficient at the µeV scale.