Density matrix renormalization group boosted by Gutzwiller projected wave functions

TL;DR

This paper introduces a method to enhance two-dimensional DMRG calculations by initializing with Gutzwiller projected states, overcoming local minima and significantly improving accuracy without extra computational cost.

Contribution

The authors propose using Gutzwiller projected states as initial guesses to boost DMRG performance in 2D, addressing local minima and enabling entanglement analysis.

Findings

Improved DMRG accuracy by orders of magnitude

Circumvented local minima in 2D DMRG

Quantified the entanglement similarity between initial and final states

Abstract

We propose to boost the performance of the density matrix renormalization group (DMRG) in two dimensions by using Gutzwiller projected states as the initialization ansatz. When the Gutzwiller projected state is properly chosen, the notorious "local minimum" issue in DMRG can be circumvented and the precision of DMRG can be improved by orders of magnitude without extra computational cost. Moreover, this method allows to quantify the closeness of the initial Gutzwiller projected state and the final converged state after DMRG sweeps, thereby sheds light on whether the Gutzwiller ansatz captures the essential entanglement features of the actual ground state for a given Hamiltonian. The Kitaev honeycomb model has been exploited to demonstrate and benchmark this new method.