US-Switzerland Cooperative Research on Correlated Electron Systems

9414840 Mihaly该奖项支持Laszlo Mihaly教授和斯托尼布鲁克的纽约州立大学（SUNY）的一名研究生，以及布鲁克海文国家实验室的Gwyn威廉姆斯博士，与瑞士洛桑联邦理工学院（EPFL）的Laszlo Forro教授在固态物理学方面进行合作。 他们将通过测量从远红外到可见光范围的光学电导率来探索选定超导材料中的电子状态。 参与者为合作带来了独特的设施和专业知识组合，用于研究薄晶体薄膜的红外透射特性。 特别是，EPFL的Forro博士开发了一种特殊的样品制备方法，用于极薄的单晶，可以对各种各向异性材料进行光学分析。 他将研究样品的磁性和电子输运特性。 大部分光谱学工作将在斯托尼布鲁克进行，而低频红外测量将在布鲁克海文国家实验室的国家同步加速器光源进行。 超导电性、自旋密度波和电荷密度波都是电子关联的表现。 虽然电子之间的相互作用和电子基态的性质对于这三种现象有着深刻的不同，但它们之间也有重要的相似之处。 这个美国-瑞士的合作研究将对三种模型材料进行实验分析，每种材料都表现出其中一种现象，以提高对导致这些有趣和潜在有用现象的电子相关性的理解。 这些结果应该是特别感兴趣的凝聚态物理学家在高温超导领域的工作。 ***

9414840 Mihaly This award supports Professor Laszlo Mihaly and a graduate student of the State University of New York (SUNY) at Stony Brook, joined by Dr. Gwyn Williams of Brookhaven National Laboratory, to collaborate in solid state physics with Professor Laszlo Forro of the Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland. They will explore electron states in selected superconducting materials by measuring the optical conductivity from the far infrared to the visible range. The participants bring to the collaboration a unique combination of facilities and expertise for the study of the infrared transmission properties of thin crystalline films. In particular, Dr. Forro at EPFL has developed a special sample preparation method for extremely thin single crystals which permits optical analyses of a variety of anisotropic materials. He will investigate the magnetic and electronic transport properties of the samples. Most of the optical spectroscopy work will be carried out at Stony Brook, while low frequency infrared measurements will be made at the National Synchrotron Light source at Brookhaven National Laboratory. Superconductivity, spin density waves and charge density waves are all manifestations of electron correlations. While the interaction between the electrons and the nature of the electronic ground state are profoundly different for these three phenomena, there are also important similarities among them. This U.S.-Swiss collaborative research will experimentally analyze three model materials each of which exhibits one of these phenomena, in order to improve understanding of the electron correlations which cause these interesting and potentially useful phenomena. The results should be of particular interest to condensed matter physicists working in the area of high temperature superconductivity. ***