Stuttgart 2012 – wissenschaftliches Programm
Q 51.2: Vortrag
Donnerstag, 15. März 2012, 14:15–14:30, V47.02
Quantum magnetism of mass-imbalanced fermionic mixtures — •Andrii Sotnikov1, Daniel Cocks1, Michiel Snoek2, and Walter Hofstetter1 — 1Goethe University, Frankfurt am Main, Germany — 2Universiteit van Amsterdam, The Netherlands
We study magnetic phases of two-component mixtures of repulsive fermions in optical lattices in the presence of mass imbalance. The analysis is based on dynamical mean-field theory (DMFT) and its real-space generalization at finite temperature. The dependencies of the transition temperature to the ordered state on the interaction strength and the imbalance parameter are studied both in two and three spatial dimensions. For a harmonic trap, we compare our results obtained by real-space DMFT to results from a local-density approximation.
Our approach allows us to calculate the entropy at different parameters of the system and discuss the cases in which mass-imbalanced mixtures can have additional advantages for reaching quantum magnetism. We point out that at half-filling with a finite value of hopping imbalance the system has additional signatures (e.g., charge-density wave) of Neel (magnetic) ordering. We also consider additional population imbalance and study transitions between different magnetic phases in this case.