Study of Correlated Insulators and Metals in Two Dimensions

该项目由佛罗里达州立大学和国家高磁场实验室的一名女助理科学家负责，主要研究硅金属氧化物半导体场效应晶体管（MOSFET）的低温输运。 硅MOSFET中的二维电子系统表现出金属-绝缘体转变，这仍然是无法解释的。 实验将导致绝缘体，金属和过渡的更深层次的特征。 该项目将包括测量绝缘相中电子态的长时间弛豫，研究自旋自由度在金属行为中的作用，研究屏蔽长度变化对所有不同制度的影响，以及不同类型的无序的影响。 实验将在大型和中型MOSFET中进行。 这些研究将与提出的理论模型进行比较。 这项研究的结果有望进一步激发和约束金属-绝缘体转变的理论，并大大提高对高度相关系统的理解。 参与该项目的研究生将接受各种实验技术的培训。 这项培训将为他们在科学和技术领域的广泛职业生涯做好准备。许多具有潜在巨大技术重要性的新材料发现它们接近金属-绝缘体转变。 在所有相关的例子中，从长期已知的掺杂半导体到最近发现的高温超导体，金属状态是通过化学掺杂其他绝缘材料而产生的。 因此，理解金属-绝缘体转变的本质是材料科学和技术的一个重要问题。 这也是凝聚态物理学中的一个基本问题。 这个项目由佛罗里达州立大学和国家强磁场实验室的一名女助理科学家负责，将集中研究二维电子系统中的金属-绝缘体转变。 测量将导致绝缘体，金属和过渡的更深入的表征，它们将为众多竞争理论提供实验测试。 该研究结果有望进一步激发和约束金属-绝缘体转变理论。 参与该项目的研究生将接受各种实验技术的培训。 这项培训将使他们为科学和技术领域的广泛职业做好准备。

This project from a female assistant scientist at Florida State University and the Natioanl High Magnetic Field Laboratory will focus on the study of low-temperature transport in Si metal-oxide-semiconductor field-effect transistors (MOSFETs). The two-dimensional electron system in Si MOSFETs exhibits a metal-insulator transition that is still unexplained. The experiments will lead to a deeper characterization of the insulator, the metal, and the transition. The project will include measurements of long-time relaxation of electronic states in the insulating phase, studies of the role of the spin degrees of freedom in the metallic behavior, studies of the effects of the variation in the screening length on all different regimes, and the effects of different types of disorder. The experiments will be carried out in both large and mesoscopicMOSFETs. The studies will be compared to the proposed theoretical models. The results of this research are expected to further stimulate and constrain theories of the metal-insulator transition, and greatly improveunderstanding of highly correlated systems in general. Graduate students involved in the project will receive training in a variety of experimental techniques. This training will prepare them for a wide range of careersin the areas of science and technology.%%%Many of the novel materials with potentially great technological importance, find themselves close to the metal-insulator transition. In all of the relevant examples, ranging from the long-known doped semiconductors to recently discovered high temperature superconductors, the metallic state is created bychemically doping an otherwise insulating material. Understanding the nature of the metal-insulatortransition thus represents an important issue for materials science and technology. It also presents a fundamental problem in condensed matter physics. This project from a female assistant scientist at Florida State University and the Natioanl High Magnetic Field Laboratory will focus on the study of the metal-insulator transition in a two-dimensional electron system. The measurements will lead to a deeper characterization of the insulator, the metal, and the transition, and they will provide an experimental test of the numerous competing theories. The results of this research are expected to further stimulate and constrain theories of the metal-insulator transition. Graduate students involved in the project will receive training in a variety of experimental techniques. This training will prepare them for a wide range of careers in the areas of science and technology.***