Heavy Fermion scaling: Uranium versus Cerium and Ytterbium compounds

Details Heavy Fermion scaling: Uranium versus Cerium and Ytterbium compounds Heavy Fermion scaling: Uranium versus Cerium and Ytterbium compounds

2011-01-20

arxiv.org/abs/1101.3992v1

Physics

Condensed Matter

Strongly Correlated Electrons

Scientific paper

In an effort to explore the differences between rare-earth-based and uranium-based heavy Fermion (HF) compounds that reflect the underlying difference between local 4$f$ moments and itinerant 5$f$ moments we analyze scaling laws that relate the low temperature neutron spectra of the primary ("Kondo-esque") spin fluctuation to the specific heat and susceptibility. While the scaling appears to work very well for the rare earth intermediate valence compounds, for a number of key uranium compounds the scaling laws fail badly. There are two main reasons for this failure. First, the presence of antiferromagnetic (AF) fluctuations, which contribute significantly to the specific heat, alters the scaling ratios. Second, the scaling laws require knowledge of the high temperature moment degeneracy, which is often undetermined for itinerant 5$f$ electrons. By making plausible corrections for both effects, better scaling ratios are obtained for some uranium compounds. We point out that while both the uranium HF compounds and the rare earth intermediate valence (IV) compounds have spin fluctuation characteristic energies of order 5 - 25 meV, they differ in that the AF fluctuations that are usually seen in the U compounds are never seen in the rare earth IV compounds. This suggests that the 5f itineracy increases the f-f exchange relative to the rare earth case.

Affiliated with

Also associated with

No associations

Rating

Heavy Fermion scaling: Uranium versus Cerium and Ytterbium compounds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Heavy Fermion scaling: Uranium versus Cerium and Ytterbium compounds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heavy Fermion scaling: Uranium versus Cerium and Ytterbium compounds will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-334517