Theoretical Study of Growing Metal and Semiconductor Nanostructures on Molecule Corrals

该奖项支持理论和计算研究和教育，以探索使用一种称为分子圈的独特模板来生长金属和半导体纳米结构的新方法。研究将集中在三个方面：(1)从第一性原理理论定量确定动力学和热力学生长参数；(2)分子圈内生长形态和动态的计算机模拟；(3)分子圈模板的生长模式和纳米结构形成的基本理论的发展。理论和计算技术将被应用于解决在微观和宏观层面提出的问题。将发展多尺度（电子-原子-连续介质）理论来研究纳米结构在分子环上的生长机制。这些包括：(1)利用第一性原理总能量方法计算吸附原子的吸附、扩散和与栅栏阶边的相互作用；(2)利用动力学蒙特卡罗方法对分子圈内二维岛屿形成、形态演化和生长动态进行原子模拟；(3)在连续介质弹性理论框架下，对应变对分子圈内二维生长的影响，特别是纳米级量子血小板、环和盘的形成进行了细观模拟；(4)电子生长模型下金属纳米片和纳米片稳定性的电子能量计算。大规模的原子模拟将在本地Beowulf集群和NSF超级计算中心的并行超级计算机上进行。我们的科学目标是为理解在图图化衬底上的异质外延生长和不同类别的材料（金属与半导体）在同一平台上的集成提供新的见解，并为建立一种新的、通用的纳米结构生长方法获得基础知识。具体目标是为理解金属（Au和Ni）和半导体（Si）纳米结构在分子环的独特模板上的生长机制奠定基础，并建立最佳的模板结构、生长条件和材料组合，以生长具有控制尺寸、形状和密度的纳米结构。这个项目将让学生参与研究，作为教育经历的一部分。该项目的计算部分将有助于丰富一门新的研究生课程，“计算材料科学——原子模拟”，该课程最近由PI为材料科学与工程专业开发。在这个项目中开发的一些计算代码将作为研究和教育的共享资源提供。将努力广泛传播这项工作，并向公众普及纳米科学和技术。该奖项支持理论和计算研究以及教育，以探索使用一种称为分子圈的独特模板来生长金属和半导体纳米结构的新方法。研究将集中在三个方面：(1)从第一性原理理论定量确定动力学和热力学生长参数；(2)分子圈内生长形态和动态的计算机模拟；(3)分子圈模板的生长模式和纳米结构形成的基本理论的发展。理论和计算技术将被应用于解决在微观和宏观层面提出的问题。将发展多尺度（电子-原子-连续介质）理论来研究纳米结构在分子环上的生长机制。其中一些工作将涉及大规模的原子模拟，这些模拟将在本地贝奥武夫集群和NSF超级计算中心的并行超级计算机上进行。科学目标是获得基础知识，建立一种新的和通用的方法来生长纳米结构。具体目标是为理解金属和半导体纳米结构在分子环模板上的生长机制奠定基础，并建立最佳的模板结构、生长条件和材料组合，以生长具有控制尺寸、形状和密度的纳米结构。这个项目将让学生参与研究，作为教育经历的一部分。该项目的计算部分将有助于丰富一门新的研究生课程，“计算材料科学——原子模拟”，该课程最近由PI为材料科学与工程专业开发。在这个项目中开发的一些计算代码将作为研究和教育的共享资源提供。将努力广泛传播这项工作，并向公众普及纳米科学技术

This award supports theoretical and computational research and education to explore a novel approach for growing metal and semiconductor nanostructures using a unique class of templates called molecule corrals. Research will focus on three areas: (1) quantitative determination of the kinetic and thermodynamic growth parameters from first-principles theory; (2) computer simulation of growth morphology and dynamics inside molecule corrals; and (3) development of fundamental theories of growth modes and nanostructure formation on the molecule-corral templates. Theoretical and computational techniques will be applied to tackle the proposed problems at both the microscopic and macroscopic level. Multiscale (electronic-atomic-continuum) theories will be developed to investigate growth mechanisms of nanostructures on molecule corrals. These include: (1) atomistic calculations of adatom adsorption, diffusion, and interaction with corral step edges using first-principles total-energy methods; (2) atomistic simulation of two-dimensional (2D) island formation, morphological evolution, and growth dynamics inside molecule corrals using kinetic Monte Carlo method; (3) mesoscopic modeling of strain effects on 2D growth inside molecule corrals, in particular the formation of nanoscale quantum platelets, rings, and disks, within the framework of continuum elastic theory; and (4) electronic energy calculation of stability of metallic nanodisks and nanomesas within the electronic growth model. Large-scale atomistic simulations will be performed on local Beowulf clusters and on parallel supercomputers at NSF supercomputing centers. A scientific objective is to provide new insights into the understanding of heteroepitaxial growth on patterned substrates and of integration of dissimilar classes of materials (metals vs. semiconductors) on the same platform and to obtain fundamental knowledge for establishing a novel and versatile approach for growing nanostructures. The specific goals are to lay the groundwork for understanding the growth mechanisms of metal (Au and Ni) and semiconductor (Si) nanostructures on the unique templates of molecule corrals and to establish the optimal template structures, growth conditions, and materials combinations for growing nanostructures with controlled size, shape, and density. This project will involve students in the research as part of the educational experience. The computational part of the project will help to enrich a new graduate-level course, "computational materials science---atomic simulations," developed recently by the PI for Materials Science and Engineering majors. Some computational codes developed in this project will be made available as shared resources for research and education. Efforts will be made to broadly disseminate the work and to educate the general public about Nanoscale science and technology.%%%This award supports theoretical and computational research and education to explore a novel approach for growing metal and semiconductor nanostructures using a unique class of templates called molecule corrals. Research will focus on three areas: (1) quantitative determination of the kinetic and thermodynamic growth parameters from first-principles theory; (2) computer simulation of growth morphology and dynamics inside molecule corrals; and (3) development of fundamental theories of growth modes and nanostructure formation on the molecule-corral templates. Theoretical and computational techniques will be applied to tackle the proposed problems at both the microscopic and macroscopic level. Multiscale (electronic-atomic-continuum) theories will be developed to investigate growth mechanisms of nanostructures on molecule corrals. Some of the work will involve large-scale atomistic simulations, which will be performed on local Beowulf clusters and on parallel supercomputers at NSF supercomputing centers. The scientific objective is to obtain fundamental knowledge for establishing a novel and versatile approach for growing nanostructures. The specific goals are to lay the groundwork for understanding the growth mechanisms of metal and semiconductor nanostructures on templates of molecule corrals and to establish the optimal template structures, growth conditions, and materials combinations for growing nanostructures with controlled size, shape, and density. This project will involve students in the research as part of the educational experience. The computational part of the project will help to enrich a new graduate-level course, "computational materials science---atomic simulations," developed recently by the PI for Materials Science and Engineering majors. Some computational codes developed in this project will be made available as shared resources for research and education. Efforts will be made to broadly disseminate the work and to educate the general public about Nanoscale science and technology.***