Thursday, February 11, 2010
NMR/μSR: Spectroscopic Tools for Probing Quantum Criticality and Magnetic Frustration in Condensed Matter Systems
Oscar Bernal
Dept. of Physics and Astronomy, California State University, Los Angeles
An introduction to the physical phenomena underlying the spectroscopic techniques of Nuclear Magnetic Resonance and Muon Spin Rotation will be given. The usefulness of these techniques for studying electronic correlations in condensed matter systems will be similarly highlighted. Disordered heavy-fermion metals and frustrated magnets will be presented as two areas of study where the techniques continue to yield valuable information. In the former category, an example system is UCu4X (X=Pd and Ni). Here, NMR/μSR data suggest a novel classification for these materials as “quantum spin glasses.” As an example of the latter category, the magnetically frustrated system NiGa2S4 will be shown to display NMR/μSR features that contradict the current assignment of this material as a viscous “spin liquid.” Some future research paths based on these results will be discussed.
Refreshments at 11:00 AM. Seminar begins at 11:10 AM.
Building 8, Room 241
For further information, please call (909) 869-4014
