Electron Transport in Quantum Dots

量子点中的电子传输

• 批准号: 9501438
• 负责人: Robert Westervelt
• 金额: $ 22.5万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 1998-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9501438&HistoricalAwards=false
• 关键词: Electron; Transport; Quantum; Dots

9501438 Westervelt Coupled two and three quantum dots, artificial molecules, including chains and rings of dots will be fabricated on gallium- arsenide/aluminum-gallium-arsenide heterostructures from UCSB. Such structures on semiconductors will enable the PI to compensate for the effect of impurities and defects on the energy of the electrons and the dot to dot coupling. Coulomb blockade and dot capacitance at ultra-low temperatures will be used as spectroscopic tools for electron states in single and couple quantum dots. Additional probes such as localized microwave excitation via miniaturized striplines, and spatially resolved scanning probe measurements currently under development will be used to characterize electron states and transport in single and coupled dots. The objective is to elucidate the nature of electron states in coupled dots and to search for possible collective quantum phenomena. The behavior of electrons inside these structures is of great current interest, both for practical and for fundamental reasons. The controlled motion of single electrons through coupled quantum dots is the basis for new approaches to electronics and computation. %%% This project investigates semiconductor "quantum dot", structures which are so small that they are also referred to as artificial atoms and molecules. Their fabrication is complex and involves collaboration between workers at Harvard and UC Santa Barbara. The behavior of electrons inside these structures is of great current interest, both for practical and for fundamental reasons. The controlled motion of single electrons through coupled quantum dots is the basis for new approaches to electronics and computation. For example, a goal is to develop single electron devices in which each bit is represented by a single electron, whose state may be optically switched. Unlike "real" molecules, the size and cou pling between the quantum dots can be varied by fabrication methods to produce new phenomena not normally found in molecules. Measurements of the Coulomb blockade and dot capacitance at ultra-low temperatures will be used as spectroscopic tools for electron states in single and coupled quantum dots. ***

9501438 Westervelt 将在 UCSB 的砷化镓/铝砷化镓异质结构上制造耦合两个和三个量子点的人造分子，包括点链和点环。 半导体上的这种结构将使PI能够补偿杂质和缺陷对电子能量和点与点耦合的影响。超低温下的库仑阻塞和点电容将用作单量子点和耦合量子点中电子态的光谱工具。 其他探针，例如通过小型化带状线进行的局部微波激发，以及目前正在开发的空间分辨扫描探针测量，将用于表征单点和耦合点中的电子状态和传输。 目的是阐明耦合点中电子态的性质并寻找可能的集体量子现象。无论出于实际原因还是出于根本原因，这些结构内的电子行为目前引起了人们极大的兴趣。单电子通过耦合量子点的受控运动是电子学和计算新方法的基础。 %%% 该项目研究半导体“量子点”，这种结构非常小，也被称为人造原子和分子。它们的制造过程非常复杂，需要哈佛大学和加州大学圣巴巴拉分校的工作人员之间的合作。 无论出于实际原因还是出于根本原因，这些结构内的电子行为目前引起了人们极大的兴趣。 单电子通过耦合量子点的受控运动是电子学和计算新方法的基础。 例如，一个目标是开发单电子器件，其中每个位都由单个电子表示，其状态可以通过光学方式切换。与“真实”分子不同，量子点的尺寸和耦合可以通过制造方法来改变，以产生分子中通常不存在的新现象。 超低温下库仑封锁和点电容的测量将用作单个和耦合量子点中电子态的光谱工具。 ***