Principal Component Analysis of Competing Correlations in Quarter-Filled Hubbard Models

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Equbal, Md Fahad, Hassan, S R, Ahsan, M. A. H.
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866917476066918400
author Equbal, Md Fahad
Hassan, S R
Ahsan, M. A. H.
author_facet Equbal, Md Fahad
Hassan, S R
Ahsan, M. A. H.
contents We present an unsupervised learning analysis of correlation hierarchies in the quarter-filled simple and extended Hubbard models by applying principal component analysis (PCA) to exact-diagonalization (ED) data on 3x4 and 4x4 cylindrical clusters. While the non-interacting limit (U=0) provides a finite-size reference, increasing on-site repulsion U induces localization and reorganizes the low-energy spectrum. For the extended model, we examine moderate (U=4) and strong (U=10) coupling regimes, where conventional structure factors reveal familiar crossovers among charge, spin and local-pairing correlations. PCA of the corresponding correlation matrices captures these crossovers directly from the data, without assuming predefined order parameters by identifying charge-dominated, spin-dominated and pairing-dominated regimes through variance condensation into leading components. This establishes PCA as a transparent, model-agnostic framework for uncovering the hierarchy and competition of correlation channels in finite Hubbard clusters, providing a bridge between exact diagonalization and modern machine-learning diagnostics in strongly correlated systems.
format Preprint
id arxiv_https___arxiv_org_abs_2511_12551
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Principal Component Analysis of Competing Correlations in Quarter-Filled Hubbard Models
Equbal, Md Fahad
Hassan, S R
Ahsan, M. A. H.
Strongly Correlated Electrons
We present an unsupervised learning analysis of correlation hierarchies in the quarter-filled simple and extended Hubbard models by applying principal component analysis (PCA) to exact-diagonalization (ED) data on 3x4 and 4x4 cylindrical clusters. While the non-interacting limit (U=0) provides a finite-size reference, increasing on-site repulsion U induces localization and reorganizes the low-energy spectrum. For the extended model, we examine moderate (U=4) and strong (U=10) coupling regimes, where conventional structure factors reveal familiar crossovers among charge, spin and local-pairing correlations. PCA of the corresponding correlation matrices captures these crossovers directly from the data, without assuming predefined order parameters by identifying charge-dominated, spin-dominated and pairing-dominated regimes through variance condensation into leading components. This establishes PCA as a transparent, model-agnostic framework for uncovering the hierarchy and competition of correlation channels in finite Hubbard clusters, providing a bridge between exact diagonalization and modern machine-learning diagnostics in strongly correlated systems.
title Principal Component Analysis of Competing Correlations in Quarter-Filled Hubbard Models
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2511.12551