相关论文: Transport through graphene-like flakes with intrin…
We present an elaborate and systematic study of the conductance properties of a zigzag bilayer graphene nanoribbon modeled by a Kane-Mele (KM) Hamiltonian. The interplay of the Rashba and the intrinsic spin-orbit couplings with the edge…
We present a microscopic theory for interacting graphene armchair nanoribbon quantum dots. Long range interaction processes are responsible for Coulomb blockade and spin-charge separation. Short range ones, arising from the underlying…
We address the interaction of graphene with 3d transition metal adatoms and the formation of localized magnetic moments by means of first-principles calculations. By comparing calculations within the generalized gradient approximation (GGA)…
We investigate the quantum transport dynamics of electrons in a multi-path Aharonov-Bohm interferometer comprising several parallel graphene nanoribbons. At low magnetic field strengths, the conductance displays a complex oscillatory…
We propose a mechanism to drive singlet-triplet spin transitions electrically, in a wide class of graphene nanostructures that present pairs of in-gap zero modes, localized at opposite sublattices. Examples are rectangular nanographenes…
Quantum confinement and interference often generate exotic properties in nanostructures. One recent highlight is the experimental indication of a magnetic phase transition in zigzag-edged graphene nanoribbons at the critical ribbon width of…
Graphene nanoribbons and constrictions are envisaged as fundamental components of future carbon-based nanoelectronic and spintronic devices. At nanoscale, electronic effects in these devices depend heavily on the dimensions of the active…
Mean-field theories have since long predicted edge magnetism in graphene nanoribbons, where the order parameter is given by the local magnetization. However, signatures of edge magnetism appears elusive in the experiments, suggesting…
Carbon-based nanostructures and graphene, in particular, evoke a lot of interest as new promising materials for nanoelectronics and spintronics. One of the most important issue in this context is the impact of external electrodes on…
We perform projective quantum Monte Carlo simulations of zigzag graphene nanoribbons within a realistic model with long-range Coulomb interactions. Increasing the relative strength of nonlocal interactions with respect to the on-site…
In honeycomb Dirac systems with broken inversion symmetry, orbital magnetic moments coupled to the valley degree of freedom arise due to the topology of the band structure, leading to valley-selective optical dichroism. On the other hand,…
Carbon-based magnetic structures promise significantly longer coherence times than traditional magnetic materials, which is of fundamental importance for spintronic applications. An elegant way of achieving carbon-based magnetic moments is…
Based on a tight-binding model and a recursive Green's function technique, spin-depentent ballistic transport through tinny graphene sheets (flakes) is studied. The main interest is focussed on: electrical conductivity, giant…
Using first-principles calculations, the effect of magnetic point defects (vacancy and adatom) is investigated in zigzag graphene nanoribbons. The structural, electronic, and spin-transport properties are studied. While pristine ribbons…
Effects of electron-electron and spin-orbit interactions on the ground-state magnetic configuration and on the corresponding thermoelectric and spin thermoelectric properties in zigzag nanoribbons of two-dimensional hexagonal crystals are…
Magnetism in graphene is an emerging field that has received much theoretical attention. In particular, there have been exciting predictions for induced magnetism through proximity to a ferromagnetic insulator as well as through localized…
We investigate the density and temperature-dependent conductance of graphene nanoribbons with varying aspect ratio. Transport is dominated by a chain of quantum dots forming spontaneously due to disorder. Depending on ribbon length,…
We investigate the effects of homogeneous and inhomogeneous deformations and edge disorder on the conductance of gated graphene nanoribbons. Under increasing homogeneous strain the conductance of such devices initially decreases before it…
Low dimensional carbon-based materials are interesting because they can show intrinsic $\pi$-magnetism associated to p-electrons residing in specific open-shell configurations. Consequently, during the last years there have been impressive…
The effects of Coulomb interactions on the electronic properties of bilayer graphene nanoribbons (BGNs) covered by a gate electrode are studied theoretically. The electron density distribution and the potential profile are calculated…