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A DMRG study of the q-symmetric Heisenberg chain

M. Kaulke·I. Peschel
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Abstract

The spin one-half Heisenberg chain with $U_q[SU(2)]$ symmetry is studied via density-matrix renormalization. Ground-state energy and $q$-symmetric correlation functions are calculated for the non-hermitian case $q=\exp(iπ/(r+1))$ with integer $r$. This gives bulk and surface exponents for (para)fermionic correlations in the related Ising and Potts models. The case of real $q$ corresponding to a diffusion problem is treated analytically.

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M. Kaulke, I. Peschel. 1998-06-22. A DMRG study of the q-symmetric Heisenberg chain. https://doi.org/10.1007/s100510050496

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