Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MP: Fachverband Theoretische und Mathematische Grundlagen der Physik
MP 5: Klassische Feldtheorie und Statistische Mechanik
MP 5.1: Vortrag
Dienstag, 18. März 2014, 17:15–17:35, SPA SR125
Thermal fluctuations and correlations in the Bose-Hubbard model — •Patrick Navez1, Konstantin Queisser2, Konstantin Krutitstky1, and Ralf Schützhold1 — 1Universtät Duisburg-Essen, Lotharstrasse 1, 47057 Duisburg, Germany — 2The University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada
For the example of the Bose-Hubbard model in the (formal) limit of large coordination numbers Z, we calculate properties of the thermal state via an expansion into powers of 1/Z. This method provides the thermal energy, the on-site reduced density matrix containing the thermal fluctuations as well as the thermal correlations between two lattice sites. Furthermore, it yields the thermal eigen-frequencies of the system and gives the phase boundary between the Mott and the superfluid state at finite temperature. Employing the hierarchy of correlations [1,2,3], these results provide the correct thermal initial state for a quantum quench of the Bose-Hubbard model.
Ref: [1] Emergence of coherence in the Mott-superfluid quench of the Bose-Hubbard model, P. Navez, R. Schützhold, Phys. Rev. A, 82 063603 (2010); [2]Quasi-particle approach for general lattice Hamiltonians, P. Navez, F. Queisser, R. Schützhold, arXiv:1303.4112; [3]Equilibration versus (pre) thermalization in the Bose and Fermi Hubbard models, F. Queisser, K. Krutitsky, P. Navez, R. Schützhold, arXiv:1311.2212.