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arXiv · 1206.0006

Short-Range Correlations and Cooling of Ultracold Fermions in the Honeycomb Lattice

Baoming Tang·Thereza Paiva·Ehsan Khatami·Marcos Rigol
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Abstract

We use determinantal quantum Monte Carlo simulations and numerical linked-cluster expansions to study thermodynamic properties and short-range spin correlations of fermions in the honeycomb lattice. We find that, at half filling and finite temperatures, nearest-neighbor spin correlations can be stronger in this lattice than in the square lattice, even in regimes where the ground state in the former is a semimetal or a spin liquid. The honeycomb lattice also exhibits a more pronounced anomalous region in the double occupancy that leads to stronger adiabatic cooling than in the square lattice. We discuss the implications of these findings for optical lattice experiments.

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Baoming Tang, Thereza Paiva, Ehsan Khatami, Marcos Rigol. 2012-11-13. Short-Range Correlations and Cooling of Ultracold Fermions in the Honeycomb Lattice. https://doi.org/10.1103/physrevlett.109.205301

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