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Exact Ground State Energy of Hubbard Rings in the Atomic Limit

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 نشر من قبل William Hodge
 تاريخ النشر 2009
  مجال البحث فيزياء
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Using a straightforward extension of the analysis of Lieb and Wu, we derive a simple analytic form for the ground state energy of a one-dimensional Hubbard ring in the atomic limit. This result is valid for an textit{arbitrary} number of lattice sites $L$ and electrons $N leq L$. Furthermore, our analysis, including an application of the theory of stochastic matrices, provides insight into the degeneracy and spin properties of the ground states in the atomic limit. We give numerical results which illustrate how the atomic limit is approached.



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