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Density matrix renormalisation group for a quantum spin chain at non-zero temperature

R. J. Bursill·T. Xiang·G. A. Gehring
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Abstract

We apply a recent adaptation of White's density matrix renormalisation group (DMRG) method to a simple quantum spin model, the dimerised $XY$ chain, in order to assess the applicabilty of the DMRG to quantum systems at non-zero temperature. We find that very reasonable results can be obtained for the thermodynamic functions down to low temperatures using a very small basis set. Low temperature results are found to be most accurate in the case when there is a substantial energy gap.

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R. J. Bursill, T. Xiang, G. A. Gehring. 1996-08-30. Density matrix renormalisation group for a quantum spin chain at non-zero temperature. https://doi.org/10.1088/0953-8984%2F8%2F40%2F003

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