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Control of the finite size corrections in exact diagonalization studies

Claudius Gros
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Abstract

We study the possibility of controlling the finite size corrections in exact diagonalization studies quantitatively. We consider the one- and two dimensional Hubbard model. We show that the finite-size corrections can be be reduced systematically by a grand-canonical integration over boundary conditions. We find, in general, an improvement of one order of magnitude with respect to studies with periodic boundary conditions only. We present results for ground-state properties of the 2D Hubbard model and an evaluation of the specific heat for the 1D and 2D Hubbard model.

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Claudius Gros. 1995-11-23. Control of the finite size corrections in exact diagonalization studies. https://doi.org/10.1103/physrevb.53.6865

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