Magnetism in strained graphene dots

Abstract

We study the magnetization of square and hexagonal graphene dots. It is shown that two classes of hexagonal dots have a second order phase transition at a critical Hubbard energy $U$, whoose value is similar to the one in bulk graphene, albeit the dots do not have a density of states proportional to the absolute value of the energy, relatively to the Dirac point. Furthermore, we show that a particular class of hexagonal dots having zig-zag edges, does not exhibit zero energy edge states. We also study the effect of uniaxial strain on the evolution of the magnetization of square dots, and find that the overall effect is an enhancement of magnetization with strain. The enhancement can be as large as 100% for strain of the order of 20%. Additionaly, stress induces a spatial displacement of the magnetization over the dot, moving it from the zig-zag to the armchair edges.

Figure and references added. Conclusions section enlarged; http://link.aps.org/doi/10.1103/PhysRevB.80.245436

References in corpus (36)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• Two Dimensional Atomic Crystals
• Energy Band Gap Engineering of Graphene Nanoribbons
• Energy Gaps in Graphene Nanoribbons
• Chaotic Dirac billiard in graphene quantum dots
• Uniaxial Strain in Graphene by Raman Spectroscopy: G peak splitting, Gruneisen Parameters and Sample Orientation
• A tight-binding approach to uniaxial strain in graphene
• All-graphene integrated circuits via strain engineering
• Quantum-limited shot noise in graphene
• Magnetism in graphene nano-islands
• Phase Coherent Transport of Charges in Graphene Quantum Billiard
• Macroscopic graphene membranes and their extraordinary stiffness
• Room-temperature ferromagnetism in graphite driven by 2D networks of point defects
• Disorder Induced Localized States in Graphene
• Vacancy induced magnetism in graphene and graphene ribbons
• Magnetism in Disordered Graphene and Irradiated Graphite
• Modeling disorder in graphene
• Tuning of energy levels and optical properties of graphene quantum dots
• Tunable stress and controlled thickness modification in graphene by annealing
• Half-metallic graphene nanodots
• $\pi$-Electron Ferromagnetism in Metal Free Carbon Probed by Soft X-Ray Dichroism
• Tunable Coulomb blockade in nanostructured graphene
• Strained graphene: tight-binding and density functional calculations
• Coherent transport in graphene nanoconstrictions
• Carrier Density and Magnetism in Graphene Zigzag Nanoribbons
• Symmetry Classes in Graphene Quantum Dots: Universal Spectral Statistics, Weak Localization, and Conductance Fluctuations
• Low density ferromagnetism in biased bilayer graphene
• Experimental Evidence for Two-Dimensional Magnetic Order in Proton Bombarded Graphite
• Edge-dependent selection rules in magic triangular graphene flakes
• Nonmagnetic-Defect-Induced Magnetism in Graphene
• Transport through evanescent waves in ballistic graphene quantum dots
• Nearly Perfect Single-Channel Conduction in Disordered Armchair Nanoribbons
• Dirac fermion quantization on graphene edges: Isospin-orbit coupling, zero modes and spontaneous valley polarization
• Stochastic dynamics of magnetization in a ferromagnetic nanoparticle out of equilibrium
• First order ferromagnetic phase transition in the low electronic density regime of a biased graphene bilayer

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• The Hubbard model on the honeycomb lattice: from static and dynamical mean-field theories to lattice quantum Monte Carlo simulations
• Strain induced edge magnetism at zigzag edge in graphene quantum dot
• Effect of Uniaxial Strain on Ferromagnetic Instability and Formation of Localized Magnetic States on Adatoms in Graphene
• Correlations in the elastic Landau level of spontaneously buckled graphene
• Spin-caloritronic transport in hexagonal graphene nanoflakes
• Strain-tuning of edge magnetism in zigzag graphene nanoribbons
• Strain-tuning of vacancy-induced magnetism in graphene nanoribbons
• Diffusion on edges of insulating graphene with intravalley and intervalley scattering
• Magnetic Phases in Periodically Rippled Graphene
• Hubbard and Heisenberg models on hyperbolic lattices: Metal-insulator transitions, global antiferromagnetism, and enhanced boundary fluctuations
• Ferromagnetism without flat bands in thin armchair nanoribbons
• Triplet $p$-wave pairing correlation in low doped zigzag graphene nanoribbons
• Electronic structure and transport in materials with flat bands: 2D materials and quasicrystals
• Charge carrier mobility degradation in graphene sheet under induced strain
• Anisotropy engineering edge magnetism in zigzag honeycomb nanoribbons
• Electronic orbital angular momentum and magnetism of graphene