Site-controlled quantum dots formed during the deposition of (Al)GaAs layers by metalorganic vapor-phase epitaxy on GaAs(111)B substrates patterned with inverted pyramids result in geometric and compositional self-ordering along the vertical axis of the template. We describe a theoretical scheme that reproduces the experimentally-observed time-dependent behavior of this process, including the evolution of the recess and the increase of Ga incorporation along the base of the template to stationary values determined by alloy composition and other growth parameters. Our work clarifies the interplay between kinetics and geometry for the development of self-ordered nanostructures on patterned surfaces, which is essential for the reliable on-demand design of confined systems for applications to quantum optics.
Indium segregation during III-V quantum wire and quantum dot formation on patterned substrates
我们报告了一个模型的非平面衬底上的金属有机物气相外延，特别是V型槽和金字塔形的凹陷，我们适用于InGaAs纳米结构的生长。该模型基于一组耦合的反应-扩散方程，一个方程用于系统中的每个方面，考虑了所有动力学过程的方面依赖性（例如，前体分解、吸附原子扩散和吸附原子寿命），并且先前已被应用于说明具有V形凹槽和金字塔形凹部的GaAs（111）B表面上的AlGaAs纳米结构的温度、浓度和时间依赖性。在本研究中，在V型槽的底部的In $_{0.12}$ Ga $_{0.88}$ As量子线的生长被用来确定一组优化的动力学参数。基于这些参数，我们模拟了生长的In $_{0.25}$ Ga $_{0.75}$ As纳米结构形成的金字塔网站控制的量子点系统，成功地产生了定性的解释，其光学性质的温度依赖性，这在以前的研究中已经报道。最后，我们提出了扫描电子和横截面原子力显微镜图像，显示以前未报告的刻面在底部的金字塔形的凹陷，允许量子点形成。
Large-Area Deterministic Stamping of 2D Materials on Arbitrarily Patterned Surfaces
Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam（范德瓦尔斯-泽曼研究所，阿姆斯特丹大学物理学院）；Advanced Research Center for Nanolithography（先进纳米光刻研究中心）；Center for Nanophotonics, AMOLF（AMOLF纳米光子学中心）；van ‘t Hoff Institute for Molecular Sciences, Universiteit van Amsterdam（范特霍夫分子科学研究所，阿姆斯特丹大学）
Ultra-transient grating spectroscopy for visualization of surface acoustics
Institute of Thermomechanics, Czech Academy of Science（捷克科学院热力学研究所）；Faculty of Nuclear Science and Physical Engineering, Czech Technical University in Prague（布拉格捷克理工大学核科学与物理工程学院）
