Strongly Correlated Electron Phenomena in Rare Earth and Actinide Intermetallics

University Of California-San Diego, La Jolla CA

Investigators

Abstract

This renewal individual investigator award is to a senior professor at the University of California, San Diego for a project to study novel electronic states and phenomena produced by strong electronic correlations in rare earth and actinide intermetallic compounds. These states and phenomena include non-Fermi liquid behavior; a "heavy fermion" state; an insulating state with an energy gap of only a few meV; and an exotic superconducting state in which the pairing of superconducting electrons may be mediated by antiferromagnetic spin fluctuations. There are several objectives of this project: to characterize the novel electronic states and phenomena, determine the conditions under which they occur, identify the underlying microscopic mechanisms, and test relevant theories. The project will involve the preparation of a wide variety of rare earth and actinide compounds, and the measurement of their fundamental electrical, thermal, and magnetic properties. Information gained from the measurements will be used to modify material parameters that will greatly facilitate the exploration of electronic phase diagrams and the search for new phenomena and f-electron materials. While these studies are of fundamental scientific interest, the materials and the electronic properties that will be investigated may have technological applications, such as thermoelectric cooling, magnetic information storage, and ferroelectric devices. An important mission of this project is the training of postdoctoral associates and graduate students at UCSD and the institutions of collaborators. The collaborations with other research groups within UCSD and at other university, national, and industrial laboratories will instill in the young investigators interdisciplinary approaches to the study of materials. %%% This renewal individual investigator award is to a senior professor at the University of California, San Diego for a project that focuses on rare earth and actinide intermetallic compounds that have unusual physical properties. These unusual properties can be traced to partially filled f-electron shells of these elements. The objective of this program is to study the novel phenomena which arise in these compounds including superconductivity, magnetism and so-called "non-Fermi liquid behavior" in which the physical properties at very low temperatures are profoundly different from classical metals. The project will involve preparing these materials and characterizing their electrical, thermal, and magnetic properties. The preparation of certain materials and the performance of specialized measurements will be performed in collaboration with researchers at UCSD and other institutions. Although this research program is directed towards answering fundamental scientific questions, technological applications, such as thermoelectric cooling, magnetic information storage, and ferroelectric devices, may be found for the materials. The training of postdoctoral associates and graduate students at UCSD and the institutions of collaborators is a significant goal of this program. These young investigators will be instilled with interdisciplinary approaches to the study of materials as a result of these collaborations with other research groups within UCSD and at other university, national, and industrial laboratories. ***