Two-Dimensional Synthetic Quantum Matter

二维合成量子物质

• 批准号: 1610618
• 负责人: Hari Manoharan
• 金额: $ 43.44万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1610618&HistoricalAwards=false
• 关键词: Two; Dimensional; Synthetic; Quantum; Matter

Non-technical abstract. The ways in which electrons move through different types of materials provide the foundations for nearly all modern electronic technology. For example, the electron flow through the semiconductor silicon can be turned on or off, or modulated like a valve, and these behaviors are the basis behind transistors, computer processors, and all electronic communication. To maintain continued progress in electronics technology, the underlying components and materials must be continuously scaled down in size. However, this progress is now stymied by the fact that critical dimensions are approaching "quantum" sizes where the position of even a single stray atom or molecule plays a measurable role in performance, and the flow of electrons is impeded by atom-size impurities and even by their own tiny weight. New materials hold the key to circumventing many of these problems, but new materials are often difficult to understand and therefore apply, due to their complex nature. This project synthesizes new electronic materials using one of the most advanced laboratory technologies available-the controlled manipulation of single atoms and molecules to build up from scratch entirely new materials that can guide electrons in ways not possible with existing materials. These new materials are built one atom at a time as a means to test how new fundamental physics can be applied to electronic technologies, such as making electrons move as if they have no weight, and making electron avoid obstacles so that their flow through electronic devices is unimpeded. The information learned from these studies feeds back into synthesizing larger versions of the same materials in bulk. In the process of conducting the calculations and experiments of this project, Ph.D. students receive education and training in the critical fields of nanotechnology and nanomaterials, and undergraduate students receive exposure to state-of-the-art research. The research team teaches courses into which current research in nanoscale science and technology is interwoven, manages a program that hosts and mentors visiting students from underrepresented-minority-serving community colleges in 10-week lab research internships, and actively makes available nanoscience educational tools and multimedia for the general public. Technical abstract. This project applies atomic and molecular manipulation to the nanoscale assembly of novel quantum materials-materials whose structural and electronic properties are dominated by quantum mechanics and give rise to either novel behavior or promising technologies. The primary experimental apparatus for these investigations are custom-built low-temperature scanning probe microscopes capable of both studying and controlling matter at atomic length scales. Beyond these tools, methods and approaches also involve tools of theoretical quantum design, developed synergistically with experiments. The overall project goal is to create synthetic two-dimensional nanomaterials exhibiting new properties and states of matter not possible in their natural-materials counterparts. The scope of this project targets exquisite control of internal quantum degrees of freedom-such as electron amplitude and phase engineering through local bond-length manipulation-to enable new electronic behavior sought in modern science and technology. Work focuses on two-dimensional materials and strain-engineered phases, involving variants of Dirac materials such as graphene and the related dichalcogenide honeycomb structure molybdenum disulfide. Local probes and application of these materials are at the forefront of experimental studies and are relevant to a burgeoning class of new designer materials. Specific experiments include: using atomic-scale strain texturing to embed pseudoelectric and pseudomagnetic gauge fields into artificial molecular graphene, and pseudoelectric fields within "artificial atoms" of other strained two-dimensional monolayers; structure and atomic manipulation of boundary states and topological confinement within the same materials; assembly of electron quasicrystals and non-periodic matter.

非技术性抽象。 电子在不同材料中的运动方式为几乎所有现代电子技术提供了基础。 例如，通过半导体硅的电子流可以被打开或关闭，或者像阀门一样被调制，这些行为是晶体管，计算机处理器和所有电子通信的基础。 为了保持电子技术的持续进步，底层组件和材料的尺寸必须不断缩小。 然而，这一进展现在受到了这样一个事实的阻碍，即临界尺寸正在接近“量子”尺寸，即使是单个杂散原子或分子的位置也会在性能中发挥可测量的作用，并且电子的流动会受到原子尺寸杂质甚至其自身微小重量的阻碍。 新材料是解决这些问题的关键，但由于其复杂的性质，新材料往往难以理解，因此难以应用。 该项目使用最先进的实验室技术之一合成新的电子材料-控制操纵单个原子和分子从头开始构建全新的材料，可以以现有材料无法实现的方式引导电子。 这些新材料是一次一个原子地构建的，以测试新的基础物理学如何应用于电子技术，例如使电子像没有重量一样移动，使电子避开障碍物，使它们在电子设备中的流动不受阻碍。 从这些研究中获得的信息反馈到批量合成更大版本的相同材料中。 在进行本项目的计算和实验的过程中，Ph.D.学生接受纳米技术和纳米材料关键领域的教育和培训，本科生接触最先进的研究。 该研究小组教授的课程，其中目前的研究在纳米科学和技术交织在一起，管理一个程序，主机和导师访问学生从代表性不足的少数民族服务社区大学在10周的实验室研究实习，并积极使纳米科学教育工具和多媒体为公众。技术摘要。 该项目将原子和分子操纵应用于新型量子材料的纳米级组装，这些材料的结构和电子特性由量子力学主导，并产生新的行为或有前途的技术。 这些研究的主要实验设备是定制的低温扫描探针显微镜，能够在原子长度尺度上研究和控制物质。除了这些工具之外，方法和途径还涉及与实验协同开发的理论量子设计工具。 该项目的总体目标是创造合成的二维纳米材料，展示出天然材料中不可能的新性质和物质状态。该项目的目标范围是精确控制内部量子自由度，例如通过局部键长操纵进行电子振幅和相位工程，以实现现代科学技术中寻求的新电子行为。工作重点是二维材料和应变工程相，涉及狄拉克材料的变体，如石墨烯和相关的二硫属化物蜂窝结构二硫化钼。 这些材料的局部探测和应用是实验研究的前沿，与新兴的新型设计材料有关。具体实验包括：使用原子尺度的应变纹理将伪电场和伪磁规范场嵌入到人造分子石墨烯中，并将伪电场嵌入到其他应变二维单层的“人造原子”中;边界状态的结构和原子操纵以及相同材料内的拓扑限制;电子准晶和非周期性物质的组装。