An improved particle swarm optimization algorithm and its application to search for new magnetic ground states in the Hubbard model

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Bibliographische Detailangaben
Hauptverfasser:	Ruan, Ze, Jiang, Xiu-Cai, Song, Ze-Yi, Zhang, Yu-Zhong
Format:	Preprint
Veröffentlicht:	2024
Schlagworte:	Strongly Correlated Electrons
Online-Zugang:	Acceder al recurso
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author	Ruan, Ze Jiang, Xiu-Cai Song, Ze-Yi Zhang, Yu-Zhong
author_facet	Ruan, Ze Jiang, Xiu-Cai Song, Ze-Yi Zhang, Yu-Zhong
contents	An improved particle swarm optimization algorithm is proposed and its superiority over standard particle swarm optimization algorithm is tested on two typical benchmark functions. By employing this algorithm to search for the magnetic ground states of the Hubbard model on the real-space square lattice with finite size based on the mean-field approximation, two new magnetic states, namely the double striped-type antiferromagnetic state and the triple antiferromagnetic state, are found. We further perform mean-field calculations in the thermodynamical limit to confirm that these two new magnetic states are not a result of a finite-size effect, where the properties of the double striped-type antiferromagnetic state are also presented.
format	Preprint
id	arxiv_https___arxiv_org_abs_2403_08587
institution	arXiv
publishDate	2024
record_format	arxiv
spellingShingle	An improved particle swarm optimization algorithm and its application to search for new magnetic ground states in the Hubbard model Ruan, Ze Jiang, Xiu-Cai Song, Ze-Yi Zhang, Yu-Zhong Strongly Correlated Electrons An improved particle swarm optimization algorithm is proposed and its superiority over standard particle swarm optimization algorithm is tested on two typical benchmark functions. By employing this algorithm to search for the magnetic ground states of the Hubbard model on the real-space square lattice with finite size based on the mean-field approximation, two new magnetic states, namely the double striped-type antiferromagnetic state and the triple antiferromagnetic state, are found. We further perform mean-field calculations in the thermodynamical limit to confirm that these two new magnetic states are not a result of a finite-size effect, where the properties of the double striped-type antiferromagnetic state are also presented.
title	An improved particle swarm optimization algorithm and its application to search for new magnetic ground states in the Hubbard model
topic	Strongly Correlated Electrons
url	https://arxiv.org/abs/2403.08587

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