Level statistics of the one-dimensional ionic Hubbard model
Abstract
In this work we analyze the spectral level statistics of the one-dimensional ionic Hubbard model, the Hubbard model with an alternating on-site potential. In particular, we focus on the statistics of the gap ratios between consecutive energy levels. This quantity is often used in order to signal whether a many-body system is integrable or chaotic. A chaotic system has typically the statistics of a Gaussian ensemble of random matrices while the spectral properties of the integrable system follow a Poisson statistics. We find that whereas the Hubbard model without alternating potential is known to be integrable and its spectral properties follow a Poissonian statistics, the presence of an alternating potential causes a drastic change in the spectral properties which resemble the one of a Gaussian ensemble of random matrices. However, to uncover this behavior one has to separately consider the blocks of all symmetries of the ionic Hubbard model.
Keywords
Cite
@article{arxiv.2203.05379,
title = {Level statistics of the one-dimensional ionic Hubbard model},
author = {Jeannette De Marco and Luisa Tolle and Catalin-Mihai Halati and Ameneh Sheikhan and Andreas M. Läuchli and Corinna Kollath},
journal= {arXiv preprint arXiv:2203.05379},
year = {2022}
}