eprintid: 17894
rev_number: 11
eprint_status: archive
userid: 244
dir: disk0/00/01/78/94
datestamp: 2014-12-18 10:08:34
lastmod: 2015-01-26 11:22:35
status_changed: 2014-12-18 10:08:34
type: doctoralThesis
metadata_visibility: show
creators_name: Böttcher, Igor
title: Dimensional BCS-BEC crossover in ultracold Fermi gases
subjects: 530
divisions: 130300
adv_faculty: af-13
abstract: We investigate thermodynamics and phase structure of ultracold Fermi gases, which can be realized and measured in the laboratory with modern trapping techniques. We approach the subject from a both theoretical and experimental perspective. Central to the analysis is the systematic comparison of the BCS-BEC crossover of two-component fermions in both three and two dimensions. A dimensional reduction can be achieved in experiments by means of highly anisotropic traps. The Functional Renormalization Group (FRG) allows for a description of both cases in a unified theoretical framework. In three dimensions we discuss with the FRG the influence of high momentum particles onto the density, extend previous approaches to the Unitary Fermi Gas to reach quantitative precision, and study the breakdown of superfluidity due to an asymmetry in the population of the two fermion components. In this context we also investigate the stability of the Sarma phase. For the two-dimensional system scattering theory in reduced dimension plays an important role. We present both the theoretically as well as experimentally relevant aspects thereof. After a qualitative analysis of the phase diagram and the equation of state in two dimensions with the FRG we describe the experimental determination of the phase diagram of the two-dimensional BCS-BEC crossover in collaboration with the group of S. Jochim at PI Heidelberg.
date: 2014
id_scheme: DOI
id_number: 10.11588/heidok.00017894
ppn_swb: 1654657492
own_urn: urn:nbn:de:bsz:16-heidok-178947
date_accepted: 2014-12-10
advisor: HASH(0x5561208daa98)
language: eng
bibsort: BOTTCHERIGDIMENSIONA2014
full_text_status: public
place_of_pub: Heidelberg
citation:   Böttcher, Igor  (2014) Dimensional BCS-BEC crossover in ultracold Fermi gases.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/17894/1/dissertation_boettcher.pdf