6533b85bfe1ef96bd12bb61e

RESEARCH PRODUCT

Néel Transition of Lattice Fermions in a Harmonic Trap: A Real-Space Dynamic Mean-Field Study

Walter HofstetterIrakli TitvinidzeN. BlümerMichiel SnoekE. V. Gorelik

subject

Condensed Matter::Quantum GasesPhysicsOptical latticeCondensed matter physicsMean field theoryQuantum mechanicsQuantum Monte CarloMonte Carlo methodGeneral Physics and AstronomyAntiferromagnetismObservableFermionNéel temperature

description

We study the magnetic ordering transition for a system of harmonically trapped ultracold fermions with repulsive interactions in a cubic optical lattice, within a real-space extension of dynamical mean-field theory. Using a quantum Monte Carlo impurity solver, we establish that antiferromagnetic correlations are signaled, at strong coupling, by an enhanced double occupancy. This signature is directly accessible experimentally and should be observable well above the critical temperature for long-range order. Dimensional aspects appear less relevant than naively expected.

https://doi.org/10.1103/physrevlett.105.065301