Claro Marcel S, Levy Ido, Gangopadhyay Abhinandan, Smith David J, Tamargo Maria C
Department of Chemistry, The City College of New York, New York, NY, 10031, USA.
INL - International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal.
Sci Rep. 2019 Mar 4;9(1):3370. doi: 10.1038/s41598-019-39821-y.
We report the growth of self-assembled BiSe quantum dots (QDs) by molecular beam epitaxy on GaAs substrates using the droplet epitaxy technique. The QD formation occurs after anneal of Bismuth droplets under Selenium flux. Characterization by atomic force microscopy, scanning electron microscopy, X-ray diffraction, high-resolution transmission electron microscopy and X-ray reflectance spectroscopy is presented. Raman spectra confirm the QD quality. The quantum dots are crystalline, with hexagonal shape, and have average dimensions of 12-nm height (12 quintuple layers) and 46-nm width, and a density of 8.5 × 10 cm. This droplet growth technique provides a means to produce topological insulator QDs in a reproducible and controllable way, providing convenient access to a promising quantum material with singular spin properties.
我们报道了利用液滴外延技术通过分子束外延在砷化镓衬底上生长自组装的BiSe量子点（QDs）。量子点的形成发生在铋液滴在硒通量下退火之后。本文展示了通过原子力显微镜、扫描电子显微镜、X射线衍射、高分辨率透射电子显微镜和X射线反射光谱进行的表征。拉曼光谱证实了量子点的质量。这些量子点是晶体，呈六边形，平均高度为12纳米（12个五元层），宽度为46纳米，密度为8.5×10¹⁰厘米⁻² 。这种液滴生长技术提供了一种以可重复和可控的方式生产拓扑绝缘体量子点的方法，为获得具有奇异自旋特性的有前途的量子材料提供了便利途径。
