Navigation überspringen
Universitätsbibliothek Heidelberg
Status: Bibliographieeintrag

Verfügbarkeit
Standort: ---
Exemplare: ---
heiBIB
 Online-Ressource
Verfasst von:Grond, Julian [VerfasserIn]   i
 Streltsov, Alexej Iwanowitsch [VerfasserIn]   i
 Lode, Axel Ulrich Jürgen [VerfasserIn]   i
 Sakmann, Kaspar [VerfasserIn]   i
 Cederbaum, Lorenz S. [VerfasserIn]   i
 Alon, Ofir E. [VerfasserIn]   i
Titel:Excitation spectra of many-body systems by linear response
Titelzusatz:general theory and applications to trapped condensates
Verf.angabe:Julian Grond, Alexej I. Streltsov, Axel U.J. Lode, Kaspar Sakmann, Lorenz S. Cederbaum, and Ofir E. Alon
E-Jahr:2013
Jahr:12 August 2013
Umfang:17 S.
Teil:volume:88
 year:2013
 number:2
 elocationid:023606
 pages:1-17
 extent:17
Fussnoten:Gesehen am 03.03.2020
Titel Quelle:Enthalten in: Physical review / A
Ort Quelle:College Park, Md., 1970
Jahr Quelle:2013
Band/Heft Quelle:88(2013), 2, Artikel-ID 023606, Seite 1-17
ISSN Quelle:1094-1622
Abstract:We derive a general linear-response many-body theory capable of computing excitation spectra of trapped interacting bosonic systems, e.g., depleted and fragmented Bose-Einstein condensates (BECs). To obtain the linear-response equations we linearize the multiconfigurational time-dependent Hartree for bosons (MCTDHB) method, which provides a self-consistent description of many-boson systems in terms of orbitals and a state vector (configurations), and is in principle numerically exact. The derived linear-response many-body theory, which we term LR-MCTDHB, is applicable to systems with interaction potentials of general form. For the special case of a δ interaction potential we show explicitly that the response matrix has a very appealing bilinear form, composed of separate blocks of submatrices originating from contributions of the orbitals, the state vector (configurations), and off-diagonal mixing terms. We further give expressions for the response weights and density response. We introduce the notion of the type of excitations, useful in the study of the physical properties of the equations. From the numerical implementation of the LR-MCTDHB equations and solution of the underlying eigenvalue problem, we obtain excitations beyond available theories of excitation spectra, such as the Bogoliubov-de Gennes (BdG) equations. The derived theory is first applied to study BECs in a one-dimensional harmonic potential. The LR-MCTDHB method contains the BdG excitations and, also, predicts a plethora of additional many-body excitations which are out of the realm of standard linear response. In particular, our theory describes the exact energy of the higher harmonic of the first (dipole) excitation not contained in the BdG theory. We next study a BEC in a very shallow one-dimensional double-well potential. We find with LR-MCTDHB low-lying excitations which are not accounted for by BdG, even though the BEC has only little fragmentation and, hence, the BdG theory is expected to be valid. The convergence of the LR-MCTDHB theory is assessed by systematically comparing the excitation spectra computed at several different levels of theory.
DOI:doi:10.1103/PhysRevA.88.023606
URL:Bitte beachten Sie: Dies ist ein Bibliographieeintrag. Ein Volltextzugriff für Mitglieder der Universität besteht hier nur, falls für die entsprechende Zeitschrift/den entsprechenden Sammelband ein Abonnement besteht oder es sich um einen OpenAccess-Titel handelt.

Volltext ; Verlag: https://doi.org/10.1103/PhysRevA.88.023606
 Volltext: https://link.aps.org/doi/10.1103/PhysRevA.88.023606
 DOI: https://doi.org/10.1103/PhysRevA.88.023606
Datenträger:Online-Ressource
Sprache:eng
K10plus-PPN:175024456X
Verknüpfungen:→ Zeitschrift

Permanenter Link auf diesen Titel (bookmarkfähig):  https://katalog.ub.uni-heidelberg.de/titel/68706702   QR-Code
zum Seitenanfang