Nuclear magnetic resonance (NMR) and muon spin rotation (muSR) techniques will be used to study electronic structure, magnetism, and superconductivity in highly correlated electron metals and alloys. The sensitivity of NMR and muSR to atomic-scale magnetism makes these techniques ideal tools to probe local effects of strong electron correlations. Our NMR and muSR studies of non-Fermi Liquid (NFL) systems show that structural disorder is also deeply involved in the mechanism for NFL behavior. Measurements of muSR linewidths and relaxation rates will further elucidate relations between disorder and quantum criticality in NFL systems. muSR studies of slow spin dynamics will be carried out in geometrically frustrated antiferromagnets. Effects of time-reversal symmetry breaking will be studied in the heavy-fermion superconductor PrOs(4)Sb(12) and related systems. A thorough examination of superconductivity and magnetism will be carried out in the newly-discovered class of Ce(n)TIn(3n+2) heavy-fermion materials, which exhibit a wide variety of anomalous magnetic and superconducting behavior. Graduate students in this program will be well prepared for research/teaching careers in both basic and applied areas. %%%
Understanding effects of correlations between electrons on magnetism and conduction in solids remains an important problem in condensed matter physics, with practical consequences for technology in several areas of materials science. This research uses magnetic resonance techniques as probes of correlated-electron behavior at the atomic level. In magnetic resonance (the best-known application of which is medical MRI) the magnetism of "spin probes" (e.g. nuclei, as in nuclear magnetic resonance) is used to "spy" on the local magnetic environment of the probes. This work will lead to better understanding of the behavior of the so-called heavy-electron metals, in which electrons behave as if they were hundreds or even thousands of times more massive than free electrons. It will be carried out in collaboration with researchers at the Los Alamos National Laboratory, and with research groups abroad (Leiden University, TRIUMF, Vancouver, and the Paul Scherrer Institute, Switzerland). Graduate students in this program will gain valuable insight into research at the national and international level, and will be well prepared for research/teaching careers in both basic and applied condensed-matter physics and materials research.
