Dynamical Effects in Mesoscale Electronic Systems

中尺度电子系统中的动力学效应

• 批准号: 0072777
• 负责人: Charles Marcus
• 金额: $ 30万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-06-15 至 2003-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0072777&HistoricalAwards=false
• 关键词: Dynamical; Effects; Mesoscale; Electronic; Systems

This research is an experimental study of dynamic mesoscopic transport phenomena in semiconductor microstructures and hybrid metals/superconductor systems. The unifying theme is the interplay between three elements: quantum coherence, disorder or chaos, and dynamics in the form of a time-dependent potential. The proposed experiments also have in common the theme of dc pumping of charge using cyclic oscillating potentials, extending recent work on adiabatic quantum pumping to include the role of decoherence, dissipation, and nonadiabatic time dependence. Besides shape-deformable quantum dots, two novel pumping devices are proposed: a pump that operates in the fractional quantum Hall regime, allowing a pumping of fractionally charged quasiparticles, and a hybrid metal-superconductor that uses the ac Josephson effect to produce a cycling time evolution of boundary conditions. This research will be carried out in a new laboratory at Harvard University. The project will support a graduate student as well as materials and supplies needed for the experiments. Other students on these projects will be supported by independent fellowships. The students will be trained in state-of-the-art nanoelectronics techniques and will be well prepared for careers in academe, industry or government. %%%Trends in microelectronics have two clear directions, smaller and faster. The study of quantum mechanical effects in electronic devices-particularly disorder or chaotic systems-is known as mesoscopic physics, where "meso" indicates intermediate in size between atoms (where quantum physics is well understood) and the realm of large, classical electronics, governed by Ohm's law and other familiar classical laws. Mesoscopic physics has seen rapid development in the last decade, predominantly as a result of advances in the fabrication of clean semiconductors devices. By comparison, little work has been done on the high-speed side, and most of what is known about quantum-coherent devices is restricted to dc. The proposed experimental work aims to investigate quantum coherent electronic devices fabricated from semiconductors and hybrid metal/superconductor devices, at high frequencies, when effects of time evolution can lead to the destruction of quantum coherence effects, but can also lead to new effects such as the pumping of electrons due to cyclic, periodic changes in the effective shape of the device. These results will impact our understanding and development of high-speed nanoelectronics. The project will support one graduate student as well as provide materials and supplies for the project. Other students working on these experiments will have outside funding from the NSF and other sources. The students will be trained in state-of-the-art nanoelectronics techniques and will be well prepared for careers in academe, industry or government.

本研究是半导体微结构和混合金属/超导体系统中动态介观输运现象的实验研究。 统一的主题是三个元素之间的相互作用：量子相干性，无序或混沌，以及依赖时间的势形式的动力学。 拟议的实验也有共同的主题直流泵电荷使用循环振荡电位，最近的工作绝热量子泵，包括退相干，耗散和非绝热时间依赖性的作用。 除了形状可变形的量子点，提出了两种新的泵浦设备：一个泵，工作在分数量子霍尔制度，允许泵的分数带电准粒子，和一个混合金属超导体，使用交流约瑟夫森效应，产生一个循环时间演化的边界条件。 这项研究将在哈佛大学的一个新实验室进行。 该项目将支持一名研究生以及实验所需的材料和用品。 参与这些项目的其他学生将得到独立奖学金的支持。学生将接受最先进的纳米电子技术的培训，并将为企业，工业或政府的职业生涯做好准备。微电子学的发展趋势有两个明确的方向：更小和更快。研究电子设备中的量子力学效应-特别是无序或混沌系统-被称为介观物理学，其中“meso”表示原子（量子物理学很好地理解）和大型经典电子学领域之间的中间尺寸，由欧姆定律和其他熟悉的经典定律支配。介观物理学在过去十年中得到了快速发展，主要是由于清洁半导体器件制造的进步。相比之下，在高速方面的工作很少，而且大多数关于量子相干器件的已知都局限于直流。 拟议的实验工作旨在研究由半导体和混合金属/超导体器件制造的量子相干电子器件，在高频下，时间演化的影响可能导致量子相干效应的破坏，但也可能导致新的效应，例如由于器件有效形状的周期性变化而产生的电子泵。 这些结果将影响我们对高速纳米电子学的理解和发展。 该项目将资助一名研究生，并为该项目提供材料和用品。 从事这些实验的其他学生将从NSF和其他来源获得外部资金。 学生将接受最先进的纳米电子技术的培训，并将为企业，工业或政府的职业生涯做好准备。