Quasi-1-D Molecular Organic Conductors: Experiment and Simulation

非技术性：我们日常使用电力和电子产品的每一件事，从通过烤面包机的电流到整个信息技术革命，都涉及到相互之间不“交谈”的电子。我们已经学会了以我们所拥有的程度来操纵电子的电荷，因为我们理解了它们如何被认为是不相互作用的，尽管相反的东西吸引、喜欢和排斥格言。磁性和超导性是这种不能说话的状态的惊人例外，但还有其他的，关于电子还有更多需要了解的东西。当电子运动被严格限制时，许多新的东西就被发现了。我们已经知道，当施加严格的平面几何(二维)时，会出现新的现象。这一条件在现代半导体材料中的实现直接导致了整数和分数量子化霍尔效应的发现。前者涉及几乎不相互交谈的电子，而对于后者，它们紧密而精致地结合在一起。本项目研究的是当电子运动被进一步限制在一维空间时，电子的性质。有一些有机和分子材料是相当好的电导体，其结构特征是电子的运动非常接近一维。同样，由于几何收缩，以及伴随而来的小尺寸量子力学效应重要性的增加，新的现象正在出现，特别是在强磁场中。这个项目研究电子在一维材料中的行为，特别是PI项目最近发现的干扰-公度磁阻振荡现象的本质。从这项研究中获得的知识将被希望设计纳米级电子和电磁结构的技术人员发现非常有用，例如使用碳纳米管，其中一维效应将占主导地位。该项目将通过暑期实习、奖学金和工作坊，在几个层面上促进学生学习和发现新材料的物理学，包括高中、本科生和研究生。技术：这个个人研究人员奖支持一个研究低维导体和超导体的实验项目。该项目的一个目标是确定准一维有机金属中角磁阻振荡的起源。最近的实验和理论提出了一种新的宏观量子效应，即干涉公度振荡，或者这可能是一种已知效应的新表现。在最高可达到的场(BC为45特斯拉，NHMFL为60特斯拉)中的角度相关的磁输运测量将被用来详细研究在TMTSF有机导体中看到的一维到二维的交叉现象。此外，利用纳米光刻和微悬臂梁技术，将首次在这些材料中探索有限尺寸效应及其对自旋密度波和自旋三重态超导电性的影响。该项目将通过暑期实习、奖学金和研讨会，在高中、本科生和研究生的几个层面上促进学生学习和发现新材料的物理学。

NON-TECHNICAL:Everything in our everyday experience with electricity and electronics, from the current running through the toaster oven to the entire information technology revolution, involves electrons that don't "talk" to each other. We have learned to manipulate the electron's charge to the extent we have because we understand how they can be considered non-interacting in spite of the opposites attract, likes repel dictum. Magnetism and superconductivity are spectacular exceptions to this nontalking state, but there are others, and there is much more to learn about the electron. Much of what is new is being found when electron motion is severely confined. We already know that new phenomena arise when strict planar geometry is imposed (two-dimensionality). Realization of this condition in modern semiconducting materials led directly to the discoveries of the integer and fractional quantized Hall effects. The former involves electrons that hardly talk to each other, while for the latter, they are intimately and exquisitely engaged. The present project deals with the nature of the electron when its motion is further confined, to one dimension. There are certain organic and molecular materials that are quite good electrical conductors, and whose structural characteristics are such that the electron motion is very nearly one-dimensional. Again, as a result of geometric constrictions, and the concomitant increase in the importance of quantum mechanical effects on small size scales, new phenomena are arising, especially in strong magnetic fields. This project investigates the behavior of electrons in one-dimensional materials, in particular the nature of the recently-discovered interference-commensurate magnetoresistance oscillation phenomena discovered by the project PI. Knowledge gained from this study will be found to be of much use by technologists wishing to devise nanoscale electronic and electromagnetic structures, for example using carbon nanotubes, where one-dimensional effects will dominate. The project will promote student learning and discovery of the physics of novel materials at several levels, high school, undergraduate, and graduate, through summer internships, fellowships and workshops.TECHNICAL:This individual investigator award supports an experimental project to investigate low-dimensional conductors and superconductors. One goal of this project is to determine the origin of angular magnetoresistance oscillations in quasi-one-dimensional organic metals. Recent experiment and theory suggest a new type of macroscopic quantum effect, interference commensurate oscillations, or perhaps this is a new manifestation of a known effect. Angle-dependent magnetotransport measurements in the highest attainable fields (45 tesla at BC, 60 tesla at NHMFL) will be used to examine in detail the 1D-to-2D dimensional crossover phenomenon seen in TMTSF organic conductors. Also, using nanolithographic and microcantilever techniques, finite size effects, and their impact on spin density waves and spin-triplet superconductivity, will be explored for the first time in these materials. The project will promote student learning and discovery of the physics of novel materials at several levels, high school, undergraduate, and graduate, through summer internships, fellowships and workshops.