Abstract Ternary IIIP1−xAsx nanowires and axial heterostructures within such nanowires are perfect building blocks for optoelectronics in an important wavelength range. However, the full control over the morphology and composition of IIIP1−xAsx nanowires as well as the interfacial abruptness of axial In(As)P/InP nanowire heterostructures is not achieved so far. Here, we present a fully self-consistent model for the growth and composition of gold-catalyzed IIIP1−xAsx nanowires and nanowire heterostructures that explains and predicts interesting phenomena. In particular, we find that the phosphorous concentration in the quaternary Au-III-As-P droplet should be much smaller than that of arsenic under the typical growth conditions. This suppresses the indium crystallization rate when passing from the InAs to InP segment, leading to the droplet swelling. Special care should be taken to keep the droplet on top of the InP segment. We show that the InAs/InP interfacial abruptness is challenging, while the reverse InP/InAs switch should always be atomically sharp. The governing equations connecting thermodynamics and kinetics of ternary nanowires based on IIIP1−xAsx are used to formulate clear routes for the necessary compositional control, with possible extensions to other material systems.

中文翻译：

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基于IIIP 1-x As x 的金催化三元纳米线和轴向纳米线异质结构的组成控制

摘要 三元 IIIP1-xAsx 纳米线和此类纳米线内的轴向异质结构是重要波长范围内光电子学的完美构建块。然而，到目前为止还没有实现对 IIIP1-xAsx 纳米线的形态和组成以及轴向 In(As)P/InP 纳米线异质结构的界面突变的完全控制。在这里，我们提出了一个完全自洽的模型，用于金催化的 IIIP1-xAsx 纳米线和纳米线异质结构的生长和组成，可以解释和预测有趣的现象。特别是，我们发现在典型的生长条件下，四元 Au-III-As-P 液滴中的磷浓度应该比砷小得多。这抑制了从 InAs 到 InP 段时的铟结晶速率，导致液滴肿胀。应特别注意将液滴保持在 InP 段的顶部。我们表明 InAs/InP 界面突变是具有挑战性的，而反向 InP/InAs 开关应该始终是原子级的。连接基于 IIIP1-xAsx 的三元纳米线的热力学和动力学的控制方程用于为必要的成分控制制定明确的路线，并可能扩展到其他材料系统。