Fundamental Experimental Properties of Mesoscopic Systems

介观系统的基本实验特性

• 批准号: 9730577
• 负责人: Richard Webb
• 金额: $ 38万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2001-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9730577&HistoricalAwards=false
• 关键词: Fundamental; Experimental; Properties; Mesoscopic; Systems

9730577 Webb This is a condensed matter physics project that investigates the quantum mechanical properties of electron transport through submicron conductors. In these very small structures the phase of the wavelength of the electron wave function are important variables that are probed by a variety of subtle experimental arrangements. The project will systematically explore the phase coherent transport properties of mesoscopic system on time scales much shorter and much longer than the phase coherence time. State- of-the-art dc superconducting quantum interference devices (SQUIDs) will be used to study the size dependence of the magnetic response of both single and arrays of metal rings. The object is an understanding of why the persistent current in phase coherent loops appears to have quantum fluctuations which are orders of magnitude larger than expected. In addition, magnetic and transport properties of mesoscopic systems whose size approaches that of the Kondo screening length will be studied. The project provides exceptional educational opportunities for graduate students and post-doctoral associates. They are involved in intellectually challenging research at the frontiers of condensed matter physics. The experiments require the latest fabrication and measurement methods and prepare the students for a wide range of scientific or technical careers. %%% This is a condensed matter physics project that employs state-of- the-art micro-fabrication methods to prepare ultra-small structures. Much of the work is focused on understanding how electrons flow through the nanoscale structures. Conventional ideas of current flow do not apply, and the wave-mechanical properties of the electron dominate the response of currents in loops, arrays of loops, films, etc. The project addresses currently unsolved problems in the quantum mechanical behav ior of the nanostructures. These problems are relevant to those involved in the microelectronics industry where the size of transistors is steadily decreasing to the so-called mesoscopic realm where quantum mechanics becomes important. An additional project deals with the properties of nano-wires containing magnetic impurity atoms. The impurities influence the electron transport in surprising and poorly understood ways. The project provides exceptional educational opportunities for graduate students and post-doctoral associates. They are involved in intellectually challenging research at the frontiers of condensed matter physics. The experiments require the latest fabrication and measurement methods and prepare the students for a wide range of scientific or technical careers. ***

9730577韦伯这是一个凝聚态物理项目，研究电子通过亚微米导体传输的量子力学性质。在这些非常小的结构中，电子波函数的波长的相位是通过各种微妙的实验排列来探测的重要变量。该项目将系统地探索介观系统在比相位相干时间短得多和长得多的时间尺度上的相位相干输运特性。最先进的直流超导量子干涉器件(SQUID)将被用来研究单个金属环和金属环阵列的磁响应的尺寸相关性。这个目标是为了理解为什么相位相干环路中的持续电流似乎具有比预期大几个数量级的量子波动。此外，还将研究尺寸接近近藤屏蔽长度的介观体系的磁性和输运性质。该项目为研究生和博士后助理提供了绝佳的教育机会。他们参与了凝聚态物理前沿的智力挑战研究。这些实验需要最新的制造和测量方法，并为学生从事广泛的科学或技术职业做好准备。这是一个凝聚态物理项目，采用最先进的微制造方法来制备超微小结构。大部分工作都集中在了解电子如何通过纳米级结构。传统的电流流动思想并不适用，电子的波力学性质决定了回路、回路阵列、薄膜等中电流的响应。该项目解决了目前尚未解决的纳米结构量子力学行为的问题。这些问题与微电子工业有关，在微电子工业中，晶体管的尺寸正在稳步缩小到所谓的介观领域，在介观领域，量子力学变得重要。另一个项目涉及含有磁性杂质原子的纳米线的性质。杂质对电子传输的影响令人惊讶，但人们对此知之甚少。该项目为研究生和博士后助理提供了绝佳的教育机会。他们参与了凝聚态物理前沿的智力挑战研究。这些实验需要最新的制造和测量方法，并为学生从事广泛的科学或技术职业做好准备。***