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arXiv · 0805.2719

Magnetism of Cold Fermionic Atoms on p-Band of an Optical Lattice

Lei Wang·Xi Dai·Shu Chen·X. C. Xie
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Abstract

We carry out \textit{ab initio} study of ground state phase diagram of spin-1/2 cold fermionic atoms within two-fold degenerate $p$-band of an anisotropic optical lattice. Using the Gutzwiller variational approach, we show that a robust ferromagnetic phase exists for a vast range of band fillings and interacting strengths. The ground state crosses over from spin density wave state to spin-1 Neel state at half filling. Additional harmonic trap will induce spatial separation of varies phases. We also discuss several relevant observable consequences and detection methods. Experimental test of the results reported here may shed some light on the long-standing issue of itinerant ferromagnetism.

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Lei Wang, Xi Dai, Shu Chen, X. C. Xie. 2008-05-20. Magnetism of Cold Fermionic Atoms on p-Band of an Optical Lattice. https://doi.org/10.1103/physreva.78.023603

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