Spin- and Circular-Polarized Resonant Photoemission

本研究的目的是确定强相关电子系统中准粒子的性质和行为，其中能带形成起着重要作用。通过将自旋分析与过渡金属2P （L3）光吸收边附近的圆偏振软x射线辐射相结合，可以避免分析非铁磁体自旋极化光发射的传统困难。这些光发射测量将首次将自旋分辨光发射光谱的应用扩展到所有的过渡金属材料，而不管它们的磁性状态（铁磁性、反铁磁性等）。新技术将应用于简单的过渡金属氧化物、高tc超导体和窄带铁磁体。这些实验将使用欧洲和美国最先进的第三代同步加速器辐射源。对磁性材料的基本认识仍然不完整，特别是对一类磁性电子相互作用强烈的材料。这些是高度相关的电子系统，包括高温超导体。该项目利用最先进的同步辐射源从磁性材料中产生光电子。对光电子的磁性（自旋极化）的分析可以得到关于磁性材料本身的关键信息。该项目的结果将检验目前在高度相关电子系统中磁性起源的理论。这些信息主要具有根本性的意义，其结果可能导致新的磁性和超导材料的发展。* * *

9625340 Sinkovich The objective of this research is to determine the nature and behavior of quasiparticles in strongly correlated electron systems, where band formation plays an important role. Conventional difficulties in analysis of spin polarized photoemission from non-ferromagnets will be circumvented by combining the spin analysis with circularly polarized soft-x-ray radiation in the vicinity of the transition metal 2P (L3) photoabsorption edge. These photo emission measurements will for the first time extend the application of spin-resolved photoemission spectroscopy to all transition metal materials irrespective of their magnetic state (ferromagnetic, antiferromagnetic, etc.). The new techniques will be applied to simple transition metal oxides, high-Tc superconductors, and narrow band ferromagnets. The experiments will use state-of-theart third generation synchrotron radiation sources in Europe and the United States. %%% The fundamental understanding of magnetic materials remains incomplete, particularly for the class of materials in which the magnetic electrons interact strongly with one another. These are highly correlated electron systems, and include the high temperature superconductors. This project exploits state-of-theart synchrotron radiation sources to produce photoemitted electrons from magnetic materials. An analysis of the magnetism (spin polarization) of the photoelectrons yields crucial information about the magnetic materials themselves. The results of the project will test current theories of the origin of magnetism in highly correlated electron systems. The information is primarily of fundamental interest and the results may lead to development of new magnetic and superconducting materials. ***