Ground-State Dynamical Correlation Functions: An Approach from Density Matrix Renormalization Group Method

TL;DR

This paper introduces a numerical method combining DMRG and maximum entropy techniques to accurately compute ground-state dynamical correlation functions in one-dimensional quantum systems.

Contribution

The authors develop a novel approach that uses sum rules and moments within DMRG to reconstruct dynamical correlation functions, enhancing computational efficiency and accuracy.

Findings

Successfully applied to spinless fermion systems

Accurately reproduces dynamical density-density correlations

Demonstrates effectiveness in related spin models

Abstract

A numerical approach to ground-state dynamical correlation functions from Density Matrix Renormalization Group (DMRG) is developed. Using sum rules, moments of a dynamic correlation function can be calculated with DMRG, and with the moments the dynamic correlation function can be obtained by the maximum entropy method. We apply this method to 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.