Numerical renormalization group study of the correlation functions of the antiferromagnetic spin-$\frac{1}{2}$ Heisenberg chain

K. A. Hallberg, P. Horsch, G. Martinez

We use the density-matrix renormalization group technique developed by White \cite{white} to calculate the spin correlation functions $<S_{n+l}^z{S}_n^z>=(-1{)}^l\omega (l,N)$ for isotr…