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On the accuracy of the density matrix renormalization group method

Ors Legeza·Gabor Fath
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Abstract

White's density matrix renormalization group ({DMRG}) method has been applied to the one-dimensional Ising model in a transverse field ({ITF}), in order to study the accuracy of the numerical algorithm. Due to the exact solubility of the {ITF} for any finite chain length, the errors introduced by the basis truncation procedure could have been directly analysed. By computing different properties, like the energies of the low-lying levels or the ground-state one- and two-point correlation functions, we obtained a detailed picture, how these errors behave as functions of the various model and algorithm parameters. Our experience with the {ITF} contributes to a better understanding of the {DMRG} method, and may facilitate its optimization in other applications.

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Ors Legeza, Gabor Fath. 1998-09-02. On the accuracy of the density matrix renormalization group method. https://doi.org/10.1103/physrevb.53.14349

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