Tyndall National Institute, University College Cork, Lee Maltings, Cork, Ireland.
Nanoscale Res Lett. 2011 Oct 26;6(1):567. doi: 10.1186/1556-276X-6-567.
We present the results of a study of nitrogen incorporation in metalorganic-vapour-phase epitaxy-grown site-controlled quantum dots (QDs). We report for the first time on a significant incorporation (approximately 0.3%), producing a noteworthy red shift (at least 50 meV) in some of our samples. Depending on the level of nitrogen incorporation/exposure, strong modifications of the optical features are found (variable distribution of the emission homogeneity, fine-structure splitting, few-particle effects). We discuss our results, especially in relation to a specific reproducible sample which has noticeable features: the usual pattern of the excitonic transitions is altered and the fine-structure splitting is suppressed to vanishing values. Distinctively, nitrogen incorporation can be achieved without detriment to the optical quality, as confirmed by narrow linewidths and photon correlation spectroscopy.
我们展示了在金属有机气相外延生长的位点控制量子点中掺入氮的研究结果。我们首次报道了显著的掺入（约 0.3%），在我们的一些样品中产生了显著的红移（至少 50 meV）。根据氮的掺入/暴露程度的不同，发现光学特性有很大的变化（发射均匀性的分布变化、精细结构分裂、少体效应）。我们讨论了我们的结果，特别是与一个具有显著特征的可重复样品有关：通常的激子跃迁模式被改变，精细结构分裂被抑制到零值。值得注意的是，氮的掺入可以在不损害光学质量的情况下实现，这一点得到了窄线宽和光子相关光谱学的证实。
