Regensburg 2010 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 15: MLT: Quantum Liquids, Bose-Einstein Condensates, Ultra-cold Atoms, ... 1
TT 15.6: Vortrag
Dienstag, 23. März 2010, 15:30–15:45, H18
Impurities in the hardcore Bose-Hubbard model and the xxz model on the triangular lattice — •Xuefeng Zhang1,2, Yuchuan Wen3, and Sebastian Eggert2 — 1Institute of theoretical physics of Chinese Academy of Science, Beijing, China — 2Department of Physics of Univ. Kaiserslautern, Ksierslautern,Germany — 3Capital Normal university, Beijing, China
The ferromagnetic-antiferromagnetic xxz model is equivalent to the hardcore Bose-Hubbard model. On a triangular lattice frustration effects give rise to interesting physical behavior, including a realization of a supersolid phase. We now consider vacancies in this model using a combination of numerical Monte Carlo simulations and analytic calculations. The solid order and the superfluid density show characteristic changes locally around the impurity depending on the phase. In some cases a single impurity can affect the physical behavior of the entire system. The results show an interesting competition of the different order parameters and illustrate the nature of the excitations in the different phases.