Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
Q: Fachverband Quantenoptik und Photonik
Q 24: Quantum Gases: Opt. Lattice 1
Q 24.3: Vortrag
Mittwoch, 16. März 2011, 11:00–11:15, HSZ 02
Adiabatic generation of a Heisenberg antiferromagnet in an optical lattice — •Michael Lubasch1, Valentin Murg2, Mari-Carmen Bañuls1, Juan Ignacio Cirac1, Ulrich Schneider3, and Immanuel Bloch1, 3 — 1Max Planck Institute of Quantum Optics, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany — 2University of Vienna, Faculty of Physics, Boltzmanngasse 5, 1090 Vienna, Austria — 3Ludwig-Maximilians-University Munich, Faculty of Physics, Schellingstrasse 4, 80799 Munich, Germany
Ultracold fermions in optical lattices hold the potential to be employed as a true quantum simulator of the Hubbard model and as such give us insight into high-Tc superconductivity. However, a main obstacle is still the low temperatures needed for the validity of the Hubbard model description.
Whereas a fermionic Mott state has already been realized in an optical lattice (R. Joerdens et al., Nature 455, 204 (2008); U. Schneider et al., Science 322, 1520 (2008)), the next challenge is the demonstration of magnetic order, present in an underlying Heisenberg antiferromagnet. However, a direct construction of this state is difficult because even lower temperatures are needed.
Alternatively, we may try to generate the antiferromagnetic state by means of adiabatic evolution from an easily preparable initial state. We numerically simulate our proposal via Matrix Product States (MPS) in 1D and Projected Entangled Pair States (PEPS) in 2D. We discuss the resulting time scales for the adiabatic evolution, the effect of defects in the initial state and the importance of a harmonic trap.