6533b86dfe1ef96bd12c9470
RESEARCH PRODUCT
Discriminating antiferromagnetic signatures in systems of ultracold fermions by tunable geometric frustration
E. V. GorelikChia-chen ChangN. BlümerRichard T. Scalettarsubject
PhysicsCondensed matter physicsHubbard modelQuantum Monte Carlomedia_common.quotation_subjectFrustrationFermionCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsQuantum mechanicsAntiferromagnetismCondensed Matter::Strongly Correlated ElectronsA determinantmedia_commondescription
Recently, it has become possible to tune optical lattices continuously between square and triangular geometries. We compute thermodynamics and spin correlations in the corresponding Hubbard model using a determinant quantum Monte Carlo technique and show that the frustration effects induced by the variable hopping terms can be clearly separated from concomitant bandwidth changes by a proper rescaling of the interaction. An enhancement of the double occupancy by geometric frustration signals the destruction of nontrivial antiferromagnetic correlations at weak coupling and entropy $s\ensuremath{\lesssim}\mathrm{ln}(2)$ (and restores Pomeranchuk cooling at strong frustration), paving the way to the long-sought experimental detection of antiferromagnetism in ultracold fermions on optical lattices.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-11-12 | Physical Review B |