International Research Fellowship Program: Infrared and Optical Studies of Quantum Phase Transitions

国际研究奖学金计划：量子相变的红外和光学研究

• 批准号: 0402699
• 负责人: Norman Armitage
• 金额: $ 7.9万
• 依托单位: Armitage Norman P
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-01 至 2005-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0402699&HistoricalAwards=false
• 关键词: International; Research; Fellowship; Program; Infrared

0402699ArmitageThe International Research Fellowship Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a sixteen-month research fellowship by Dr. Norman P. Armitage to work with Dr. Dirk van der Marle at the University of Geneva in Switzerland. This project concerns the study of optical and infrared properties of condensed matter systems near so-called quantum phase transition (QPTs). This a topic at the forefront of some of the most challenging and interesting problems in condensed matter physics. Once thought to be a theoretical curiosity, it is becoming increasingly clear that the existence of nearby QPTs may hold the key to understanding the unusual behavior of many systems at the forefront of condensed matter physics. The optical and infrared response of correlated electron systems, such as superconductors and novel magnetic states, are being investigated as they are tuned via an external parameter (e.g. pressure, carrier density, or magnetic field) through such a transition between various magnetic and superconducting ground states near absolute zero temperature. The work is being done in the group of Prof. Dirk van der Marel at the University of Geneva using both the state-of-the-art facilities of Dr. van der Marel's lab and new infrared systems being currently installed at the Swiss Light Source (SLS) synchrotron. Prof. van der Marel's present work concentrates on the low energy excitation spectra of strongly correlated electron systems, using various infrared and optical spectroscopic probes. The lab in Geneva is uniquely equipped for this project as one of the top laboratories in the world for such investigations. However, the optical study of pressure-tuned QPTs (such as those found in heavy fermion systems), necessitates the use of small beam spots for coupling into a diamond anvil pressure cells. This is a requirement incompatible with traditional lab based infrared or optical sources, but made possible by the advent of infrared synchrotron radiation (IRSR) sources. One of the unique aspects of this project is the use of newly commissioned infrared beamlines at the SLS.

0402699ARMITAGETHE国际研究奖学金计划使美国科学家和工程师能够在国外进行三到二十四个月的研究。 该计划的奖项为联合研究提供了机会，并在国外使用独特或补充设施，专业知识和实验条件。该奖项将支持Norman P. Armitage博士的16个月研究奖学金，以与瑞士日内瓦大学的Dirk van der Marle博士合作。该项目涉及对所谓的量子相变（QPTS）附近冷凝物质系统的光学和红外特性的研究。 这个话题位于凝结物理学中一些最具挑战性和有趣的问题的最前沿。 一旦被认为是一种理论上的好奇心，越来越清楚的是，附近QPT的存在可能是理解许多系统在凝结物理学的最前沿的异常行为的关键。 相关电子系统（例如超导体和新型磁状态）的光学和红外响应正在通过外部参数（例如压力，载体密度或磁场）调整，并通过在绝对零温度接近绝对零温度的各种磁性和超导基础状态之间进行过渡。 这项工作是在日内瓦大学的Dirk van der Marel教授的小组中完成的，使用Van der Marel博士实验室的最先进设施和目前安装在瑞士灯源（SLS）Synchrotron的新红外系统。 Van der Marel教授的当前工作集中在使用各种红外和光谱探针的强相关电子系统的低能激发光谱上。 日内瓦的实验室为该项目提供了独特的配备，是世界上最重要的调查实验室之一。 但是，压力调节的QPT的光学研究（例如在重型费米昂系统中发现的QPT）需要使用小型梁斑点将其耦合到钻石砧压力细胞中。 这是与传统的基于实验室的红外或光学源不兼容的要求，但由于红外同步辐射（IRSR）来源的出现而成为可能。 该项目的独特方面之一是在SLS上使用新委托的红外光束线。