GROUND-STATE DYNAMICAL CORRELATION-FUNCTIONS - AN APPROACH USING THE DENSITY-MATRIX RENORMALIZATION-GROUP METHOD

A numerical approach to ground-state dynamical correlation functions f rom the density-matrix renormalization group (DMRG) is developed. Usin g sum rules, moments of a dynamic correlation function can be calculat ed with DMRG, and with the moments the dynamical correlation function can be obtained by the maximum entropy method. We apply this method to a one-dimensional spinless fermion system, which can be converted to the spin-1/2 Heisenberg model in a special case. The dynamical density -density correlation function is obtained.