Related papers: Antiferromagnetism in hexagonal graphene structure…
The unusual electronic and optical properties of armchair and zigzag graphene nanoribbons (GNRs) subject to in-plane transverse electric and perpendicular magnetic fields have been systematically investigated. Our calculations were carried…
Both experimental and theoretical studies of the magnetic properties of micrographite and nanographite indicate a crucial role of the partial oxidation of graphitic zigzag edges in ferromagnetism. In contrast to total and partial…
We use quantum Monte Carlo simulations to study effects of free edges in the two-dimensional spin-1/2 Heisenberg antiferromagnet. We find that the magnetic response of an edge is smaller than the bulk susceptibility. This counter-intuitive…
The stability of the magnetization in Lieb graphene quantum dots (GQD) against disorder is studied. Such systems exhibit the degenerate shell of edge states in the middle of the energy gap occupied by spin polarized electrons. Disorder…
Nanographite systems, where graphene sheets of the orders of the nanometer size are stacked, show novel magnetic properties, such as, spin-glass like behaviors, and the change of ESR line widths while gas adsorptions. Recently, it has been…
We study theoretically the coherent electron focusing in graphene nanoribbons. Using semiclassical and numerical tight binding calculations we show that perfect armchair edges give rise to equidistant peaks in the focusing spectrum. In the…
A quasiclassical theory of giant magnetoresistance in nanoscale point contacts between different ferromagnetic metals is developed. The contacts were sorted by three types of mutual positions of the conduction spin-subband bottoms which are…
We investigate the edge-state magnetism of graphene nanoribbons using projective quantum Monte Carlo simulations and a self-consistent mean-field approximation of the Hubbard model. The static magnetic correlations are found to be short…
Using a first principles density functional electronic structure method, we study the energy gaps and magnetism in bilayer graphene nanoribbons as a function of the ribbon width and the strength of an external electric field between the…
Magnetism in narrow-band systems arises from the interplay between electronic correlations, quantum geometry, and band dispersion. In particular, both ferro and anti-ferro magnets are known to occur as ground states of (different) models…
The magnetic structures and interedge magnetic couplings of Fe, Co and Ni transition-metal terminated graphene nanoribbons with zigzag (ZGNR) and armchair (AGNR) edges are studied by first-principles calculations. Fe-ZGNR is found to show…
The $S=1/2$ Heisenberg antiferromagnet on the floret-pentagonal lattice with two kinds of interaction strength is studied by the numerical-diagonalization method. It is known that, near the five-ninth of the saturation magnetization, this…
We present a novel comprehensive first-principles theoretical study of the electronic properties and relative stabilities of edge-oxidized zigzag graphene nanoribbons. The oxidation schemes considered include hydroxyl, carboxyl, ether, and…
The microscopic basis for the stability of itinerant ferromagnetism in correlated electron systems is examined. To this end several routes to ferromagnetism are explored, using both rigorous methods valid in arbitrary spatial dimensions, as…
Using first-principles density-functional theory, we study the electronic structure of multilayer graphene nanoribbons as a function of the ribbon width and the external electric field, applied perpendicular to the ribbon layers. We…
Using a density functional theory based electronic structure method and semi-local density approximation, we study the interplay of geometric confinement, magnetism and external electric fields on the electronic structure and the resulting…
We study transport properties of hexagonal zigzag graphene quantum rings connected to semi-infinite nanoribbons. Open two-fold symmetric structures support localized states that can be traced back to those existing in the isolated six-fold…
Altermagnets feature vanishing net magnetization, like antiferromagnets, but exhibit time-reversal symmetry breaking and momentum-dependent spin-split band structures. Motivated by the prevalence of altermagnetic materials with…
The ground state of the spin-$1/2$ Heisenberg antiferromagnet on a distorted triangular lattice is studied using a numerical-diagonalization method. The network of interactions is the $\sqrt{3}\times\sqrt{3}$ type; the interactions are…
Linear conductance of junctions formed by graphene flakes with order of nanometer-thick electrodes attached at the corners of the flakes is studied. The explored structures have sizes up to 20000 atoms and the conductance is studied as a…