Quantum electron solids and interaction-driven phenomena in two- and one-dimensional systems

非技术：电子是微小的量子力学物体，存在于所有物理系统中，大多数系统都包含大量的电子。了解电子如何相互作用以及如何与环境相互作用是一个重要的科学课题，并在推动现代科学和技术方面发挥了关键作用。与水类似，电子在高温时既表现为气态，又表现为低温时的液态。另一种形式是预测但从未观测到的固态。获得电子这种固态的证据不仅对于理解最基本的力如何从根本上影响量子态很重要，而且还可以让科学家开发出非凡的未来量子电子学和自旋电子学。这些能源可持续系统对自然至关重要。随着半导体技术的极大改进，一种新型的超高纯度半导体已经成为可能，这是最近一项突破的结果，最近已经获得了初步结果，作为真正的量子电子固体的证据。这个项目利用这样的设备，用最先进的科学工具进行实验：纳米制造和超低温物理。我们的目标是捕捉量子力学机制在动力学性质上的直接证据。该项目支持一名博士生追求发现和先进技术的教育，并允许该组织与当地高中开展外联活动。技术：引人注目的新量子现象，如偶分母分数量子霍尔效应和拓扑绝缘体，是对粒子间强烈的库仑相互作用的响应。然而，最显著的相互作用驱动效应，即电子的维格纳结晶，还没有得到很好的证实。这种迷人的量子物质(具有自旋有序)不仅对基础科学至关重要，而且对包括量子电子学和自旋电子学在内的未来应用也很重要。长期以来，实验工作一直受到阻碍，因为大多数器件都包含高水平的无序，这种无序在低电子密度下会压倒相互作用效应。自2003年以来，在提供超高质量的二维电子系统方面取得了突破性进展。在超高纯场效应晶体管(称为HIGFET)的测量方面取得的最新成果使我们观察到了真正的WC。此外，初步结果还指出了可能的量子钉扎/去钉扎机制，这些机制尚不清楚。该项目利用这些具有创纪录的低电子密度的设备在MK温度下进行输运实验。我们的目标是验证远远低于经典极限的动力学性质的量子性质。采用改变温度、密度和相互作用等多种技术来研究相界面。利用交直流激励技术直接探测维格纳晶体中集体的大规模量子隧道效应。该项目支持一名博士生寻求发现和学习先进技术的教育，这些都是追求科学职业的优秀培训所不可或缺的。

Nontechnical: Electrons are tiny quantum mechanical objects that exist in all physical systems and most systems contain a large number of them. Understanding how electrons interact with each other and with the environment 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 is a solid state which was predicted but never observed. To obtain evidence of this solid state of electrons is not only important in understanding how the most basic force can radically affect the quantum states, but also allows scientists to develop remarkable future quantum electronics and spintronics. These energy sustainable systems are fundamentally important to nature. With greatly improved semiconductor technologies, a novel type of semiconductors of ultra-high purity has become available as a result of a recent breakthrough and preliminary results have been recently obtained as evidence of a genuine quantum electron solid. This project utilizes such devices to perform experiments with the most advanced scientific tools: nanofabrication and ultra-low temperature physics. The goal is to capture the direct evidence for the quantum mechanical mechanisms in the dynamical properties. This project supports the education of one Ph.D. student in pursuing discovery and advanced technologies, and allows the group to conduct outreach activities with local high schools. Technical: Remarkable new quantum phenomena, such as the even-denominator Fractional Quantum Hall Effect and Topological Insulators, emerge in response to strong inter-particle Coulomb interaction. However, the most prominent interaction-driven effect, Wigner crystallization of electrons, has not been well established. This fascinating quantum matter (with spin ordering) is not only paramount to fundamental science, but also important for future applications including quantum electronics and spintronics. 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. Since 2003, breakthroughs have been made in providing ultra-high quality two-dimensional electron systems in GaAs semiconductor field-effect-transistors. Recent achievement with the measurement of ultrahigh purity GaAs field-effect transistors (named HIGFET) has led to the observation of a genuine WC. Moreover, the preliminary results also point to possible quantum pinning/depinning mechanisms that are not understood. This project utilizes these types of devices with record low electron densities to perform transport experiments at mK temperatures. The goal is to verify the quantum nature of the dynamical properties well below the classical limits. Various techniques such varying temperature, density, and interaction are adopted to study the phase boundaries. AC+DC excitation technique is utilized to directly probe the collective, large-scale quantum tunneling in a Wigner Crystal. This project supports the education of one Ph.D. student in pursuing discovery and in learning advanced technologies, which are indispensable for excellent training in pursuing scientific careers.