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arXiv · 2210.06999

GaAs quantum dots under quasi-uniaxial stress: experiment and theory

Xueyong Yuan·Saimon F. Covre da Silva·Diana Csontosova·Huiying Huang·Christian Schimpf·Marcus Reindl·Junpeng Lu·Zhenhua Ni·Armando Rastelli·Petr Klenovsky
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Abstract

The optical properties of excitons confined in initially-unstrained GaAs/AlGaAs quantum dots are studied as a function of a variable quasi-uniaxial stress. To allow the validation of state-of-the-art computational tools for describing the optical properties of nanostructures, we determine the quantum dot morphology and the in-plane components of externally induced strain tensor at the quantum dot positions. Based on these \textsl{experimental} parameters, we calculate the strain-dependent excitonic emission energy, degree of linear polarization, and fine-structure splitting using a combination of eight-band ${\bf k}\cdot{\bf p}$ formalism with multiparticle corrections using the configuration interaction method. The experimental observations are quantitatively well reproduced by our calculations and deviations are discussed.

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Xueyong Yuan, Saimon F. Covre da Silva, Diana Csontosova, Huiying Huang, Christian Schimpf, Marcus Reindl, Junpeng Lu, Zhenhua Ni, Armando Rastelli, Petr Klenovsky. 2022-10-13. GaAs quantum dots under quasi-uniaxial stress: experiment and theory. https://doi.org/10.1103/physrevb.107.235412

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