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The Non-Abelian Density Matrix Renormalization Group Algorithm

I. McCulloch·M. Gulacsi
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Abstract

We describe here the extension of the density matrix renormalization group algorithm to the case where Hamiltonian has a non-Abelian global symmetry group. The block states transform as irreducible representations of the non-Abelian group. Since the representations are multi-dimensional, a single block state in the new representation corresponds to multiple states of the original density matrix renormalization group basis. We demonstrate the usefulness of the construction via the one-dimensional Hubbard model as the symmetry group is enlarged from $U(1) \times U(1)$, up to $SU(2) \times SU(2)$.

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I. McCulloch, M. Gulacsi. 2001-10-24. The Non-Abelian Density Matrix Renormalization Group Algorithm. https://doi.org/10.1209/epl%2Fi2002-00393-0

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