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Block-Spin Approach to Electron Correlations

P. Monthoux
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Abstract

We consider an expansion of the ground state wavefunction of quantum lattice many-body systems in a basis whose states are tensor products of block-spin wavefunctions. We demonstrate by applying the method to the antiferromagnetic spin-1/2 chain that by selecting the most important many-body states the technique affords a severe truncation of the Hilbert space while maintaining high accuracy.

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P. Monthoux. 1997-06-30. Block-Spin Approach to Electron Correlations. https://doi.org/10.1103/physrevb.56.11653

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