Comparison of the electronic structure ofInAs/GaAspyramidal quantum dots with different facet orientations

摘要: Using a pseudopotential plane-wave approach, we have calculated the electronic structure of strained InAs pyramidal quantum dots embedded in GaAs matrix, for few height $(h)$-to-base$(b)$ ratios, corresponding to different facet orientations ${101}$, ${113},$ and ${105}$. We find that dot shape (not just size) has significant effect on its structure. In particular, while binding energies ground electron hole states increase with pyramid volumes ${(b}^{2}h)$, splitting $p\ensuremath{-}$like conduction increases orientation $(h/b),$ $p\ensuremath{-}$to-$s$ decreases as base size $(b)$ increases. also there are up six bound (12 counting spin), all degeneracies other than spin, removed. This is accord conclusion electron-addition capacitance data, but contrast simple k\ensuremath{\cdot}p calculations, which predict only single level.