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arXiv:cond-mat/9906224 · Journal of Physics A Mathematical and General

Density matrices for a chain of oscillators

Ingo Peschel, Ming-Chiang Chung

Published Nov 17, 1999• 85 citations
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Abstract

We consider chains with an optical phonon spectrum and study the reduced density matrices which occur in density-matrix renormalization group calculations. Both for one site and for half of the chain, these are found to be exponentials of bosonic operators. Their spectra, which are correspondingly exponential, are determined and discussed. The results for large systems are obtained from the relation to a two-dimensional Gaussian model.

DOI
10.1088/0305-4470/32/48/305

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