Many-Body Effects in the Thermodynamic Properties of Fermi Liquids and the Electron-Phonon System and in the Excitation Spectrum of Liquid Helium-4

In this thesis I study two separate topics in many-body physics. In the first part I consider many-body effects in the thermodynamic properties of Fermi liquids and of the electron-phonon system. Using normal liquid ('3)He as an example, I show that the T('3)lnT corrections due to spin fluctuations account for the finite temperature corrections to the leading term in the specific heat. I also calculate and compare the statistical and the dynamical quasiparticle spectra and show that differences between them partially account for the discrepancy between the present and previous results. Spin fluctuation parameters determine from fits to specific heat of UPt(,3) and UAl(,2) are examined and applicability of simple spin-fluctuation models to these systems is discussed. In addition I consider the T('3)lnT contributions to the specific heat of metals due to the electron-phonon coupling and show how they may be viewed as being analogous to those from spin fluctuations.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Coffey, Dermot

• Physics, Condensed Matter

Language dc:language

eng

Identifier

(UMI)AAI8701465

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/77392