CAREER: Topological Excitations in Two Dimensional Systems

职业：二维系统中的拓扑激发

• 批准号: 9733949
• 负责人: Sheena Murphy
• 金额: $ 32.5万
• 依托单位: University of Oklahoma Norman Campus
• 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 2003-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9733949&HistoricalAwards=false
• 关键词: CAREER; Topological; Excitations; Two; Dimensional

Murphy 9733949 This is a CAREER Award to a female scientist. The research deals with special types of electronic excitations which occur as spatially extended quasiparticles in two-dimensional electron systems. It is often advantageous to sort such excitations according to whether or not they have a non-zero winding number or twist. Excitations possessing a twist are known as "topological excitations" and include solitons, vortices, domain walls and dislocations. They cannot decay for the same reason you cannot untwist a phone cord without picking up the receiver: the excitation or winding can only be removed by a large scale reorientation of the entire system. This translates to long term stability as evidenced by the use of a topological excitation known as a soliton as a signal carrier in transcontinental fiber links. The concept of a topological excitation has proven exceptionally useful in physics: Rather than attempt to describe the behavior of the entire system, a more manageable approach focuses on just the stable configuration of these excitations. Thus the tornadoes in a storm, the dislocations in a crystal or the domain walls in a ferromagnet are studied to obtain a great deal about the system at hand. This proposal details an extensive study of the topological excitations occurring on two-dimensional electronic systems in a magnetic field. %%% This is CAREER Award to a female scientist. The research deals with special types of electronic excitations known as topological excitations. These excited electron states possess a kind of twist, like a screw. Previously studied as mathematical oddities, they have recently been found in nature in two-dimensional semiconductor structures, known as Quantum Hall systems. These stable excitations are more than a new language for many body electron interactions, they are real spatially extended quasiparticles. The experimental goal of this proposal is a greater understanding of the role of topological excitations in two dimensional electronic systems. The second focus of this CAREER proposal is the adaptation of novel instructional approaches, commonly used at the introductory level, to upper level physics courses. While introductory physics education has benefited from these new techniques, there has been little application to more advanced undergraduate material. The plan is to introduce concept based questions in conjunction with group learning techniques into the more advanced curricula and to facilitate this introduction by the development of a concept question website.

墨菲9733949 这是一个给女科学家的职业奖。研究了二维电子系统中作为空间扩展准粒子的特殊类型的电子激发。 通常有利的是，根据这些激励是否具有非零绕组数或 忒斯特 具有扭曲的激励是 已知 称为“拓扑激发”，包括孤子、涡旋、畴壁和位错。它们不能衰减，就像你不能在不拿起听筒的情况下解开电话线一样：激励或绕组只能通过整个系统的大规模重新定位来消除。这转化为长期稳定性，如通过在横贯大陆的光纤链路中使用称为孤子的拓扑激励作为信号载波所证明的。 拓扑激发的概念已被证明在物理学中非常有用：而不是试图描述整个系统的行为，更易于管理的方法只关注这些激发的稳定配置。 因此，通过研究风暴中的龙卷风、晶体中的位错或铁磁体中的畴壁，我们可以获得关于这个系统的大量信息。该建议详细介绍了在磁场中的二维电子系统上发生的拓扑激发的广泛研究。 这是给一位女科学家的职业奖。该研究涉及被称为拓扑激发的特殊类型的电子激发。 这些受激电子态具有一种扭曲，就像一个螺旋。以前被研究为数学上的奇异现象，最近在自然界中的二维半导体结构中发现了它们，称为量子霍尔系统。 这些稳定的激发对许多体电子来说不仅仅是一种新的语言 互动， 它们是真实的 空间 扩展准粒子 的 该建议的实验目标是更好地理解拓扑激发在二维电子系统中的作用。职业生涯的第二个重点 建议是改编小说 教学方法，通常用于入门级，以上级物理课程。虽然入门物理教育受益于这些新技术，但很少应用于更高级的本科材料。计划在更高级的课程中结合小组学习技巧引入基于概念的问题，并通过开发概念问题网站来促进这一引入。