Altermagnetic phases and phase transitions in Lieb-$5$ Hubbard model

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Biswas, Sougata, Achintyaa, Dutta, Paramita
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915741472653312
author Biswas, Sougata
Achintyaa
Dutta, Paramita
author_facet Biswas, Sougata
Achintyaa
Dutta, Paramita
contents The emergence of altermagnetism, the collinear magnetic phase characterized by momentum-dependent spin-split bands but zero net magnetization, has fundamentally reshaped the classification of magnetic order. We propose an altermagnetic (AM) order in a repulsive Hubbard model on the Lieb-$5$ lattice. Considering only nearest-neighbor hoppings within the lattice, we show a phase transition from the nonmagnetic to a unique AM isolated band metal phase (AMIM), allowing clear identification of spin-split states. Additionally, the AM metallic phase (AMM) is also shown to appear as an intermediate phase during the transition from the normal metal to the AMIM in the presence of the diagonal hopping within each unit cell of the Lieb-$5$ lattice. The manifestation of distinct AM phases and the phase transitions, driven by Hubbard interaction and hopping integrals, have been explored in terms of spin-resolved band structure, spectral function, and the behavior of the AM order parameter. The stability of these AM phases against the spin-orbit coupling and temperature is also established.
format Preprint
id arxiv_https___arxiv_org_abs_2601_14200
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Altermagnetic phases and phase transitions in Lieb-$5$ Hubbard model
Biswas, Sougata
Achintyaa
Dutta, Paramita
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Materials Science
The emergence of altermagnetism, the collinear magnetic phase characterized by momentum-dependent spin-split bands but zero net magnetization, has fundamentally reshaped the classification of magnetic order. We propose an altermagnetic (AM) order in a repulsive Hubbard model on the Lieb-$5$ lattice. Considering only nearest-neighbor hoppings within the lattice, we show a phase transition from the nonmagnetic to a unique AM isolated band metal phase (AMIM), allowing clear identification of spin-split states. Additionally, the AM metallic phase (AMM) is also shown to appear as an intermediate phase during the transition from the normal metal to the AMIM in the presence of the diagonal hopping within each unit cell of the Lieb-$5$ lattice. The manifestation of distinct AM phases and the phase transitions, driven by Hubbard interaction and hopping integrals, have been explored in terms of spin-resolved band structure, spectral function, and the behavior of the AM order parameter. The stability of these AM phases against the spin-orbit coupling and temperature is also established.
title Altermagnetic phases and phase transitions in Lieb-$5$ Hubbard model
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Materials Science
url https://arxiv.org/abs/2601.14200