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arXiv · 0911.1818

Antiferromagnetism of Repulsively Interacting Fermions in a harmonic trap

Jianqing Qi·Lei Wang·Xi Dai
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Abstract

We propose a Real-Space Gutzwiller variational approach and apply it to a system of repulsively interacting ultracold fermions with spin 1/2 trapped in an optical lattice with a harmonic confinement. Using the Real-Space Gutzwiller variational approach, we find that in system with balanced spin-mixtures on a square lattice, antiferromagnetism either appears in a checkerboard pattern or forms a ring and antiferromagnetic order is stable in the regions where the particle density is close to one, which is consistent with the recent results obtained by the Real-Space Dynamical Mean-field Theory approach. We also investigate the imbalanced case and find that antiferromagnetic order is suppressed there.

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Jianqing Qi, Lei Wang, Xi Dai. 2009-11-10. Antiferromagnetism of Repulsively Interacting Fermions in a harmonic trap. https://doi.org/10.1088/0256-307x%2F27%2F8%2F083102

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