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Correlated Fermions on a Checkerboard Lattice

F. Pollmann·J. J. Betouras·K. Shtengel·P. Fulde
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Abstract

A model of strongly correlated spinless fermions hopping on a checkerboard lattice is mapped onto a quantum fully-packed loop model. We identify a large number of fluctuationless states specific to the fermionic case. We also show that for a class of fluctuating states, the fermionic sign problem can be gauged away. This claim is supported by numerically evaluating the energies of the low-lying states. Furthermore, we analyze in detail the excitations at the Rokhsar-Kivelson point of this model thereby using the relation to the height model and the single-mode approximation.

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F. Pollmann, J. J. Betouras, K. Shtengel, P. Fulde. 2006-12-01. Correlated Fermions on a Checkerboard Lattice. https://doi.org/10.1103/physrevlett.97.170407

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