Journal of Physics Condensed Matter
The density matrix renormalization group and critical phenomena
Robert J. Bursill, Fatma Göde
Abstract
We adapt White`s (1992, 1993) density matrix renormalization group (DMRG) to the direct study of critical phenomena. We use the DMRG to generate transformations in the space of coupling constants. We postulate that a study of density matrix eigenvalues leads to a natural identification of renormalized blocks, operators and Hamiltonians. We apply the scheme to the phase transition in the anisotropic spin-1/2 Heisenberg chain. In the simplest case where the two most probable states in odd-sized blocks are used to construct approximate renormalization group transformations, we find qualitative improvement upon the standard real-space renormalization group method for the thermal exponent nu .