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arXiv · 1206.5418

Superlattice formed by quantum-dot sheets: density of states and IR absorption

F. T. Vasko·V. V. Mitin
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Abstract

Low-energy continuous states of electron in heterosrtucture with periodically placed quantum-dot sheets are studied theoretically. The Green's function of electron is governed by the Dyson equation with the self-energy function which is determined the boundary conditions at quantum-dot sheets with weak damping in low-energy region. The parameters of superlattice formed by quantum-dot sheets are determined using of the short-range model of quantum dot. The density of states and spectral dependencies of the anisotropic absorption coefficient under mid-IR transitions from doped quantum dots into miniband states of superlattice strongly depend on dot concentration and on period of sheets. These dependencies can be used for characterization of the multi-layer structure and they determine parameters of different optoelectronic devices exploiting vertical transport of carriers through quantum-dot sheets.

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F. T. Vasko, V. V. Mitin. 2012-06-23. Superlattice formed by quantum-dot sheets: density of states and IR absorption. https://doi.org/10.1103/physrevb.85.235321

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