Signatures of Delocalization in the Fermionic 1D Hubbard Model with Box Disorder: Comparative Study with DMRG and R-DMFT

TL;DR

This study explores how disorder and interactions affect localization in the 1D Hubbard model, using R-DMFT and DMRG, revealing Mott insulator, Anderson localization, and potential delocalization phases with distinct spectral and localization properties.

Contribution

It provides a comparative analysis of R-DMFT and DMRG in identifying phases and signatures of delocalization in the disordered 1D Hubbard model.

Findings

Identification of Mott insulating and Anderson localized regimes.

Evidence of a possible delocalized phase at intermediate interaction and disorder.

Distinct scaling behaviors of local density of states, energy gap, and inverse participation number.

Abstract

We investigate the 1D Anderson-Hubbard model at half filling with box-disorder. The ground state phase diagram is obtained by means of real-space dynamical mean-field theory (R-DMFT) and the density matrix renormalization group (DMRG). We find Mott insulating and Anderson localized regimes as well as a strong indication of a delocalized phase for intermediate interaction and disorder strength within accessible system sizes. These phases are characterized and distinguished by qualitatively different scaling behavior of the local density of states, the energy gap in the excitation spectrum and the inverse participation number.