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Local quantum criticality in confined fermions on optical lattices

M. Rigol·A. Muramatsu·G. G. Batrouni·R. T. Scalettar
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Abstract

Using quantum Monte Carlo simulations, we show that the one-dimensional fermionic Hubbard model in a harmonic potential displays quantum critical behavior at the boundaries of a Mott-insulating region. A local compressibility defined to characterize the Mott-insulating phase has a non-trivial critical exponent. Both the local compressibility and the variance of the local density show universality with respect to the confining potential. We determine a generic phase diagram, that allows the prediction of the phases to be observed in experiments with ultracold fermionic atoms trapped on optical lattices.

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M. Rigol, A. Muramatsu, G. G. Batrouni, R. T. Scalettar. 2003-09-25. Local quantum criticality in confined fermions on optical lattices. https://doi.org/10.1103/physrevlett.91.130403

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