Full, three-quarter, half and quarter Wigner crystals in Bernal bilayer graphene

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Aguilar-Méndez, Enrique, Neupert, Titus, Wagner, Glenn
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866910059722702848
author Aguilar-Méndez, Enrique
Neupert, Titus
Wagner, Glenn
author_facet Aguilar-Méndez, Enrique
Neupert, Titus
Wagner, Glenn
contents Application of a displacement field opens a gap and enhances the Van-Hove singularities in the band structure of Bernal-stacked bilayer graphene. By adjusting the carrier density so that the Fermi energy lies in the vicinity of these singularities, recent experiments observe a plethora of highly correlated electronic phases including isospin polarized phases and high-resistance states with non-linear electric transport indicative of a possible Wigner crystal. We perform Hartree-Fock calculations incorporating long-range Coulomb interactions and allowing for translational and rotational symmetry breaking. We obtain the displacement field vs. carrier density phase diagram which shows isospin polarized metallic phases tracking the Van-Hove singularity in the valence band. Between these metallic phases we observe regions where the ground state is a Wigner crystal. The isospin polarization of the Wigner crystals tracks the isospin polarization of the nearby metallic phases. Depending on whether we have four, three, two or one isospin flavours, we obtain a full, three-quarter, half or quarter Wigner crystal.
format Preprint
id arxiv_https___arxiv_org_abs_2505_09685
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Full, three-quarter, half and quarter Wigner crystals in Bernal bilayer graphene
Aguilar-Méndez, Enrique
Neupert, Titus
Wagner, Glenn
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Application of a displacement field opens a gap and enhances the Van-Hove singularities in the band structure of Bernal-stacked bilayer graphene. By adjusting the carrier density so that the Fermi energy lies in the vicinity of these singularities, recent experiments observe a plethora of highly correlated electronic phases including isospin polarized phases and high-resistance states with non-linear electric transport indicative of a possible Wigner crystal. We perform Hartree-Fock calculations incorporating long-range Coulomb interactions and allowing for translational and rotational symmetry breaking. We obtain the displacement field vs. carrier density phase diagram which shows isospin polarized metallic phases tracking the Van-Hove singularity in the valence band. Between these metallic phases we observe regions where the ground state is a Wigner crystal. The isospin polarization of the Wigner crystals tracks the isospin polarization of the nearby metallic phases. Depending on whether we have four, three, two or one isospin flavours, we obtain a full, three-quarter, half or quarter Wigner crystal.
title Full, three-quarter, half and quarter Wigner crystals in Bernal bilayer graphene
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2505.09685