Award Date

12-1-2020

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Physics and Astronomy

First Committee Member

Andrew Cornelius

Second Committee Member

Ravhi Kumar

Third Committee Member

Qiang Zhu

Fourth Committee Member

Oliver Tschauner

Number of Pages

195

Abstract

Heavy fermion systems have attracted a great deal of interest since the discovery of the phenomenon in the 1970s. Over the past 35 years, the research in this field revealed a variety of unprecedented properties that the conventional theoretical framework considered conflicting or impossible. The subset of intermetallic compounds containing rare earth and actinide elements is of special interest, as these materials exhibit a range of exotic properties associated with 4f or 5f electrons. A thorough examination of the reports in the literature indicates a delicate interplay between the competing ground states, giving rise to anomalous properties including non-Fermi liquid behavior, unconventional superconductivity, Kondo effect, mixed valence, and unusual magnetic ordering. Given the sensitivity of the competing interactions to external parameters, pressure becomes a crucial non-thermal tuning factor for investigating the exotic properties of these materials and for mapping the rich P-T phase spaces.

Our project focused on the synthesis and characterization of multiple uranium based compounds. The 5f electrons are frequently found in the intermediate range between localized and delocalized states in U-based heavy fermion systems. The investigated samples were fabricated at Los Alamos National Laboratory and were probed with X-ray absorption, X-ray emission, and X- ray diffraction spectroscopic techniques at the Advances Photon Source at Argonne National Laboratory. The performed experiments contribute to the understanding of the underlying mechanisms that occur in strongly correlated systems, since a comprehensive theoretical model is

yet to be formulated.

Keywords

Synthesis; X Ray absorption; X Ray diffraction spectroscopy

Disciplines

Physics

File Format

pdf

File Size

3700 KB

Degree Grantor

University of Nevada, Las Vegas

Language

English

Rights

IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/


Included in

Physics Commons

Share

COinS