Role of Noise in Nanostructure Formation: A Theoretical Investigation of Quantum Dots and Quantum Dot Molecules

Monika Dhankhar; Madhav Ranganathan

doi:10.1063/5.0073670

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arXiv · 2108.06680

Role of Noise in Nanostructure Formation: A Theoretical Investigation of Quantum Dots and Quantum Dot Molecules

Monika Dhankhar·Madhav Ranganathan

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Abstract

We theoretically model the formation of quantum dots(QDs) and quantum dot molecules(QDMs) in silicon germanium heteroepitaxy by explicitly incorporating the role of noise in a continuum theory for surface evolution in molecular beam epitaxy. Using the connection between flux and noise, we explain how changing flux can lead to a transition from QD to QDM formation, as seen in experiments. In these systems we show a dual role of noise in nanostructure growth; one where it promotes formation of QDMs via pit nucleation, and another where it curtails QDM formation due to stochastic effects.

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Monika Dhankhar, Madhav Ranganathan. 2021-08-15. Role of Noise in Nanostructure Formation: A Theoretical Investigation of Quantum Dots and Quantum Dot Molecules. https://doi.org/10.1063/5.0073670

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