Circumferential confinement consequence on the magnetic properties of a punctured nanotube in the presence of an axial electric field

Abstract

In this paper, we present magnetic properties of a finite graphene sheet with a triangle punctured vacancy, and its counterpart single-wall carbon nanotube as a rolled-up graphene sheet in the framework of the Hubbard model in the presence of an axial electric field, in order to form a comparison study between these two graphene samples. We have noticed that the tight-binding part of the Hamiltonian consists of two types of zero-energy states in the case of the graphene sheet, the strict zero-energy states, and the quasi zero-energy states. The first type takes part in a ferromagnetic coupling between the triangle edges and one edge of the rectangle graphene sheet, while the latter one has an antiferromagnetic alignment with the opposite edge of the rectangle graphene sheet. Involving the Coulomb interaction through Hubbard term, we have observed that the slope of the cluster edge states in nanotube is higher than the graphene sheet. Additionally, spin-depolarization happens in single-wall nanotube sooner than the graphene sheet by slightly increasing an axial electric field. Also, the graphene sheet is more robust than the single wall nanotube at low electric fields.

Antiferromagnetic Ordering in Bowtie and AA‐Stacking Bilayer Trapezoidal Graphene Nanoflakes: A Comparison Study

“…The mean-field Hubbard term is added to the TB Hamiltonian to involve effective on-site coulombic interaction of p z electrons. [36][37][38][39] In parallel, some density functional calculations have been done through this study to make the results of our model Hamiltonian more reliable.…”

Impact of Topological Edge Defects on Spin Transport Properties of Zigzag Graphene Nanoribbons

“…It has plentiful physical properties, specifically the edge effect in the case of zigzag GNs, which depend firmly on the boundary's geometry [7][8][9] and the onset of magnetization in nanographene, which is not a certain characteristic in carbon-based materials. [10][11][12] Graphene has tremendous potential in electronics for the notably great mobility of its charge carriers at room temperature. The absence of energy gap in graphene makes it a metallic behaving material.…”

“…Density functional theory (DFT) and other theoretical efforts confirm the existence of sublattice-polarized states. [12,37,38] These edge-localized states proposing magnetic alignment can be accomplished in Herein, the spin-dependent transport properties of a zigzag graphene nanoribbon (zGNR) with edges decorated with a fluoranthene group are studied. Atomically perfect zigzag edge, including phenyl-edge functionalization, was synthesized by Ruffieux et al in a bottom-up chemical technique.…”

“…Such a strategy has been utilized effectively in late theoretical studies. [12,39] Furthermore, practical strategies for explaining the quantum spin-transport properties of defective zGNRs have been outlined using first-principle calculations and a Landauer-Buttiker approach so as to be able to make an assessment investigation between the model Hamiltonian and DFT calculations.…”

“…Density functional theory (DFT) and other theoretical efforts confirm the existence of sublattice‐polarized states. [ 12,37,38 ] These edge‐localized states proposing magnetic alignment can be accomplished in physical systems. Moreover, topological edge engineering during the cyclodehydrogenation process in zigzag graphene nanoribbons (zGNRs) could suggest intriguing spin‐dependent transport properties in the mentioned nanostructure.…”