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Renormalization algorithm for the calculation of spectra of interacting quantum systems

D. Porras·F. Verstraete·J. I. Cirac
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Abstract

We present an algorithm for the calculation of eigenstates with definite linear momentum in quantum lattices. Our method is related to the Density Matrix Renormalization Group, and makes use of the distribution of multipartite entanglement to build variational wave--functions with translational symmetry. Its virtues are shown in the study of bilinear--biquadratic S=1 chains.

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D. Porras, F. Verstraete, J. I. Cirac. 2005-08-08. Renormalization algorithm for the calculation of spectra of interacting quantum systems. https://doi.org/10.1103/physrevb.73.014410

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