Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 3: Correlated Electrons: Spin Systems and Itinerant Magnets 1
TT 3.5: Vortrag
Montag, 23. März 2009, 11:15–11:30, HSZ 304
Numerical evidence of a U(1) liquid phase in the quantum dimer model on a diamond lattice — •Olga Sikora1, Frank Pollmann2, Nic Shannon3, Karlo Penc4, and Peter Fulde1,5 — 1Max Planck Institute for the Physics of Complex Systems, Noethnitzer Str. 38, 01187 Dresden, Germany — 2Department of Physics, University of California, Berkeley, CA94720, USA — 3H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK — 4Research Institute for Solid State Physics and Optics, H-1525 Budapest, P.O.B. 49, Hungary — 5Asia Pacific Center for Theoretical Physics, Pohang, Korea
Quantum dimer models (QDMs) are widely studied as effective models for many different condensed matter systems. Recently, it has been suggested that in the QDM on a bipartite lattice in 3D, a U(1) liquid extends for a finite range of parameters bordering the “Rokhsar-Kivelson” (RK) point [1,2]. We have used large-scale Green’s function Monte Carlo simulations to establish the complete zero-temperature phase diagram for a QDM on a diamond lattice. Our results confirm explicitly the existence of the three phases conjectured for this model — a 16-sublattice ordered “R state” with cubic symmetry, a set of isolated states and, separating them, a U(1) liquid phase terminating at the RK point. Notably, our results for the liquid phase reproduce the energy spectra predicted by the corresponding U(1) theory.
[1] R. Moessner and S.L. Sondhi, Phys. Rev. B 68, 184512 (2003).
[2] D.L. Bergman, G.A. Fiete, and L. Balents, Phys. Rev. B 73, 134402 (2006).