Hubbard model on decorated lattices.

نویسندگان

  • C D Batista
  • B S Shastry
چکیده

We introduce a family of lattices for which the Hubbard model and its natural extensions can be quasiexactly solved, i.e., solved for the ground and low energy states. In particular, we show rigorously that the ground state of the Hubbard model with off-site Coulomb repulsions on a decorated Kagomè lattice is an ordered array of local currents. The low energy theory describing this chiral state is an S=1 / 2 XY model, where each spin degree of freedom represents the two possible chiralities of each local current.

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عنوان ژورنال:
  • Physical review letters

دوره 91 11  شماره 

صفحات  -

تاریخ انتشار 2003