Correlated fermions on a checkerboard lattice.

  title={Correlated fermions on a checkerboard lattice.},
  author={F. Pollmann and Joseph J. Betouras and Kirill Shtengel and Peter Fulde},
  journal={Physical review letters},
  volume={97 17},
A model of strongly correlated spinless fermions 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 numerical evaluation of the low-lying states. Furthermore, we analyze excitations at the Rokhsar-Kivelson point of this model using the relation to the height… 
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