期刊
APPLIED SURFACE SCIENCE
卷 444, 期 -, 页码 260-266出版社
ELSEVIER
DOI: 10.1016/j.apsusc.2018.03.098
关键词
Molecular beam epitaxy; Quantum dot; Quantum ring; Wetting layer; Capping rate; Dissolution process
类别
资金
- Spanish MICINN-MINECO [MAT2013-47102-C2-2-R, MAT2016-77491-C2-1-R]
- Dutch Foundation for Fundamental Research on Matter (FOM)
The practical realization of epitaxial quantum dot (QD) nanocrystals led before long to impressive experimental advances in optoelectronic devices, as well as to the emergence of new technological fields. However, the necessary capping process is well-known to hinder a precise control of the QD morphology and therefore of the possible electronic structure required for certain applications. A straightforward approach is shown to tune the structural and optical properties of InAs/GaAs QDs without the need for any capping material different from GaAs or annealing process. The mere adjust of the capping rate allows controlling kinetically the QD dissolution process induced by the surface In-Ga intermixing taking place during overgrowth, determining the final metastable structure. While low capping rates make QDs evolve into more thermodynamically favorable quantum ring structures, increasing capping rates help preserve the QD height and shape, simultaneously improving the luminescence properties. Indeed, a linear relationship between capping rate and QD height is found, resulting in a complete preservation of the original QD geometry for rates above similar to 2.0 ML s(-1). In addition, the inhibition of In diffusion from the QDs top to the areas in between them yields thinner WLs, what could improve the performance of several QD-based optoelectronic devices. (C) 2018 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据