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Density-matrix renormalization-group method in momentum space

T. Xiang
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Abstract

A momentum-space approach of the density-matrix renormalization-group (DMRG) method is developed. Ground state energies of the Hubbard model are evaluated using this method and compared with exact diagonalization as well as quantum Monte-Carlo results. It is shown that the momentum-space DMRG is a very useful numerical tool for studying the Hubbard model and other fundamental models of interacting electrons in two dimensions. For the Hubbard model in two dimensions, the momentum-space DMRG method reproduces accurately the exact diagonalization results of ground state energies on a $4\times 4$ lattice and yields new upper bounds of ground state energies on an 8$\times$8 lattice.

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T. Xiang. 1996-03-04. Density-matrix renormalization-group method in momentum space. https://doi.org/10.1103/physrevb.53.r10445

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