eprintid: 25592
rev_number: 13
eprint_status: archive
userid: 4090
dir: disk0/00/02/55/92
datestamp: 2018-11-14 06:03:00
lastmod: 2019-01-07 09:36:43
status_changed: 2018-11-14 06:03:00
type: doctoralThesis
metadata_visibility: show
creators_name: Beinke, Raphael
title: Excitations and dynamics of Bose-Einstein condensates: A many-body approach
subjects: ddc-530
divisions: i-130001
adv_faculty: af-12
abstract: This thesis explores the dynamics and especially the low-energy spectra of Bose-Einstein condensates (BECs) in one- and two-dimensional potential traps. Of particular interest are many-body effects. To obtain numerically exact results for the dynamics, the well-established multiconfigurational time-dependent Hartree for bosons (MCTDHB) method is applied. Excited states are calculated utilizing the recently introduced linear-response theory atop it (LR-
MCTDHB). The core of the latter theory is an in general non-hermitian eigenvalue problem. The newly developed implementation of this theory is described in detail and benchmarked towards the exactly-solvable harmonic-interaction model. Several applications are discussed.
With respect to dynamics, it is shown that both the out-of-equilibrium tunneling dynamics and the dynamics of trapped vortices are of many-body nature. Furthermore, many-body
effects in the excitation spectra are presented for BECs in different trap geometries. It is demonstrated that even for essentially-condensed systems, the spectrum of the lowest-in-energy excitations computed at the many-body level differs substantially from a standard mean-field description. In general, it is shown that bosons carrying angular momentum are more sensitive to many-body effects, both in the dynamics and the excitation spectrum.
date: 2018
id_scheme: DOI
id_number: 10.11588/heidok.00025592
ppn_swb: 1653295570
own_urn: urn:nbn:de:bsz:16-heidok-255921
date_accepted: 2018-11-07
advisor: HASH(0x561a62998690)
language: eng
bibsort: BEINKERAPHEXCITATION2018
full_text_status: public
citation:   Beinke, Raphael  (2018) Excitations and dynamics of Bose-Einstein condensates: A many-body approach.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/25592/1/Diss_RB.pdf