A DMRG study of the q-symmetric Heisenberg chain

The spin one-half Heisenberg chain with Uq[SU(2)] symmetry is studied via density-matrix renormalization. Ground-state energy and q-symmetric correlation functions are calculated for the non-Hermitian case \(\) 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.