Local classical correlations between physical electrons in Hubbard systems

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Bellomia, Gabriele, Amaricci, Adriano, Capone, Massimo
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908998387630080
author Bellomia, Gabriele
Amaricci, Adriano
Capone, Massimo
author_facet Bellomia, Gabriele
Amaricci, Adriano
Capone, Massimo
contents We demonstrate that the local nonfreeness, an unbiased measure of correlation between electrons at a single lattice site, can be computed as the mutual information between local natural spin orbitals. This leads us to prove a general result: local electron correlations in Hubbard-type models that conserve the orbital- and spin-resolved electron number are fully classical, since the local reduced density matrix is separable in the natural basis and no quantum correlations beyond entanglement are present. Finally, we compare different theoretical descriptions of magnetic and nonmagnetic states, showing that local classical correlations are drastically influenced by nonlocal processes. These results confirm the relation between local classical correlations within an open system and nonlocal entanglement and they provide a clear path for the study of the relationship between traditional quantum resources and the nonfreeness in terms of experimentally accessible quantities.
format Preprint
id arxiv_https___arxiv_org_abs_2506_18709
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Local classical correlations between physical electrons in Hubbard systems
Bellomia, Gabriele
Amaricci, Adriano
Capone, Massimo
Strongly Correlated Electrons
Quantum Physics
We demonstrate that the local nonfreeness, an unbiased measure of correlation between electrons at a single lattice site, can be computed as the mutual information between local natural spin orbitals. This leads us to prove a general result: local electron correlations in Hubbard-type models that conserve the orbital- and spin-resolved electron number are fully classical, since the local reduced density matrix is separable in the natural basis and no quantum correlations beyond entanglement are present. Finally, we compare different theoretical descriptions of magnetic and nonmagnetic states, showing that local classical correlations are drastically influenced by nonlocal processes. These results confirm the relation between local classical correlations within an open system and nonlocal entanglement and they provide a clear path for the study of the relationship between traditional quantum resources and the nonfreeness in terms of experimentally accessible quantities.
title Local classical correlations between physical electrons in Hubbard systems
topic Strongly Correlated Electrons
Quantum Physics
url https://arxiv.org/abs/2506.18709