Electron-Electron Interaction Driven Phase Transition in Low Dimensional Systems

低维系统中电子-电子相互作用驱动的相变

• 批准号: 1105183
• 负责人: Jian Huang
• 金额: $ 34万
• 依托单位: Wayne State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105183&HistoricalAwards=false
• 关键词: Electron; Interaction; Driven; Phase; Transition

****Technical Abstract****The study of the many-body electron systems encompasses two of the most fundamental subjects: electron-electron interaction and electron-disorder interaction. It is well known that sufficient disorder causes electron states to undergo Anderson Transition. On the other hand, whether strong electron-electron interaction also brings radical changes, such as the predicted Wigner Crystallization (electron solid), is still unknown. For a long time, experimental effort was hindered because most devices contain a high level of unwanted disorder which overwhelms the interaction effect at low electron densities. Recent breakthroughs have been made in providing ultra-high quality two-dimensional electron systems in GaAs semiconductor field-effect-transistors. This project will utilize this type of devices with record low electron densities to perform transport experiments at low temperatures. The goal is to verify whether strong electron-electron interaction drives a first-order phase transition (Wigner crystallization) or some intermediate phases. Either observation will provide insights in understanding the quantum mechanical nature of strongly interacting electrons in the form of a solid or a strongly correlated liquid. This project will support the education of one Ph.D. student in pursuing discovery and in learning most advanced technologies, which has historically shown to be excellent training for scientific careers.****Non-Technical Abstract****Electrons are quantum mechanical objects that exist in all physical systems and most systems contain a large number of them. Understanding the states of electrons, how they interact with the environment and each other, is a vital scientific subject and has played a critical role in advancing modern science and technologies. Analogous to water, electrons manifest both gaseous states at high temperatures and liquid states at low temperatures. Another form of the states is solid which was predicted but never observed. To obtain evidence of this solid state of electrons is not only important to understand how the most basic force among the electrons can radically affect the quantum states, but also allow scientists to utilize remarkable properties in developing quantum electronics and spintronics. As nanotechnology marks the opening of the 21st century, semiconductor technologies have greatly improved. A novel type of semiconductors of ultra-high purity has become available as a result of a recent breakthrough. This project will utilize such devices to perform experiments with the most advanced scientific tools: nanofabrication and ultra-low temperature physics. The goal is to capture direct evidences that either indicate an electron solid, or some other complex states. This project will support the education of one Ph.D. student in pursuing discovery and in learning most advanced technologies, and allow the group to conduct outreach activities with local high schools.

****技术摘要****多体电子系统的研究涵盖了两个最基本的主题：电子电子相互作用和电子disorder互动。众所周知，足够的疾病会导致电子状态进行安德森过渡。另一方面，强烈的电子电子相互作用是否还带来了根治性的变化，例如预测的Wigner结晶（电子固体）仍然未知。长期以来，由于大多数设备都包含高水平的不良疾病，这会阻碍实验性的努力，从而使低电子密度下的相互作用效果不堪重负。最近在GAAS半导体野外效应 - 传播器中提供超高质量的二维电子系统方面取得了突破。该项目将利用具有创纪录的低电子密度的这种类型的设备在低温下进行运输实验。目的是验证强的电子电子相互作用是驱动一阶相变（Wigner结晶）还是某些中间相。任何一个观察结果都将提供见解，以理解以固体或强相关液体形式的强相互作用的量子机械性质。该项目将支持一项博士学位的教育。在追求发现和学习最先进的技术方面，学生在历史上证明是对科学职业的出色培训。了解电子的状态，它们如何与环境互动，是一个至关重要的科学主题，并且在推进现代科学和技术方面发挥了关键作用。类似于水，电子在高温下在高温下表现出气态状态。状态的另一种形式是坚固的，这是预测但从未观察到的。为了获得这种固态的电子状态，不仅要了解电子中最基本的力量如何从根本上影响量子状态，而且还允许科学家在开发量子电子和纺纱型中利用显着的特性。由于纳米技术标志着21世纪的开放，半导体技术已大大改善。由于最近的突破，已经获得了一种新型的超高纯度半导体。该项目将利用此类设备使用最先进的科学工具进行实验：纳米制作和超低温度物理。目的是捕获指示电子固体或其他一些复杂状态的直接证据。该项目将支持一项博士学位的教育。学生追求发现和学习最先进的技术，并允许小组与当地高中进行外展活动。