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Atomistic theory of electronic and optical properties of InAs/InP self-assembled quantum dots on patterned substrates

Weidong Sheng·Pawel Hawrylak
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Abstract

We report on a atomistic theory of electronic structure and optical properties of a single InAs quantum dot grown on InP patterned substrate. The spatial positioning of individual dots using InP nano-templates results in a quantum dot embedded in InP pyramid. The strain distribution of a quantum dot in InP pyramid is calculated using the continuum elasticity theory. The electron and valence hole single-particle states are calculated using atomistic effective-bond-orbital model with second nearest-neighbor interactions, coupled to strain via Bir-Pikus Hamiltonian. The optical properties are determined by solving many-exciton Hamiltonian for interacting electron and hole complexes using the configuration-interaction method. The effect of positioning of quantum dots using nanotemplate on their optical spectra is determined by a comparison with dots on unpatterned substrates, and with experimental results. The possibility of tuning the quantum dot properties with varying the nano-template is explored.

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Weidong Sheng, Pawel Hawrylak. 2005-05-05. Atomistic theory of electronic and optical properties of InAs/InP self-assembled quantum dots on patterned substrates. https://doi.org/10.1103/physrevb.72.035326

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