Physical Sciences and Mathematics Commons^™

Quantum And Classical Transport Of 2d Electrons In The Presence Of Long And Short Range Disorder, Jesse Kanter

Dissertations, Theses, and Capstone Projects

This work focuses on the study of electron transport of 2-D electron gas systems in relation to both fundamental properties of the systems such as disorder and scattering mechanisms, as well as unique magnetoresistance (MR) effects. A large portion of the discussion is built around the use of an in plane magnetic field to vary the ratio between the Zeeman energy between electrons of different spins and the Landau level spacing, creating a tool to control the quantization of the density of states (DOS).

This tool is first used to isolate Quantum Positive Magnetoresistance (QPMR), which grants insight to the …

Quantum Fields In Extreme Backgrounds, Leandro Medina De Oliveira

Arts & Sciences Electronic Theses and Dissertations

Quantum field theories behave in interesting and nontrivial ways in the presence of intense electric and/or magnetic fields. Describing such behavior correctly, particularly at finite (nonzero) temperature and density, is of importance for particle physics, nuclear physics, astrophysics, condensed matter physics, and cosmology. Incorporating these conditions as external parameters also provides useful probes into the nonperturbative structure of gauge theories.

In this work, formalism for describing matter in a variety of extreme conditions is developed and implemented. We develop several expansions of one-loop finite temperature effects for spinor particles in the presence of magnetic fields, including the effects of confinement, …

Two-Photon Excitation Of Cesium Alkali Metal Vapor 72D, 82D Kinetics And Spectroscopy, Ricardo C. Davila

Theses and Dissertations

Pulsed excitation on the two-photon Cs 6²S_½ → 7²D_3/2,5/2 transition results in time-resolved fluorescence at 697 nm and 672 nm. The rates for fine structure mixing between the 7²D_3/2,5/2 states have been measured for helium and argon rare gas collision partners. The mixing rates are very fast, 1.26 ± 0.05 x 10^-9 cm³/(atom sec) for He and 1.52 ± 0.05 x 10^-10 cm³ /(atom sec) for Ar, driven by the small energy splitting and large radial distribution for the valence electron. …

Band Filling And Temperature Effects On Electrical Conductivity In Strongly Correlated Hybridized Electron Systems, Dylan T. Meyer

All Graduate Theses, Dissertations, and Other Capstone Projects

We investigate the effects of band filling as well as temperature change on the electrical conductivity of materials with strong interelectron interaction as well as band hybridization. This is done by use of the irreducible two-particle Green function method applied to strongly correlated electron systems described by the Periodic Anderson Model. It was found that there is a definite peak in electrical conductivity at low band occupancy when the d-energy sub-band is half filled. Conductivity was found to have a sharp drop with an increase in temperature as a result of thermal dispersion as well as a change in the …