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arXiv · 2311.18682

Electronic and spectral properties of Ge1-xSnx quantum dots: an atomistic study

Krzysztof Gawarecki·Jakub Ziembicki·Paweł Scharoch·Robert Kudrawiec
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Abstract

In this paper, we study theoretically the electron and spectral properties of Ge1-xSnx systems, including alloys, cubic- and spherical quantum dots. The single-particle electron and hole states are calculated within the sp3d5s* tight-binding approach and used in further modeling of the optical properties. We systematically study the interplay of Sn-driven indirect-direct band-gap transition and the quantum confinement effect in systems of reduced dimensionality. We demonstrate the regime of sizes and composition, where the ground state in Ge1-xSnx quantum dot is optically active. Finally, we calculate absorbance spectra in experimentally-relevant colloidal quantum dots and demonstrate a satisfactory agreement with experimental data.

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Krzysztof Gawarecki, Jakub Ziembicki, Paweł Scharoch, Robert Kudrawiec. 2023-11-30. Electronic and spectral properties of Ge1-xSnx quantum dots: an atomistic study. https://arxiv.org/abs/2311.18682

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