Results 1 - 10 of 12818
Results 1 - 10 of 12818. Search took: 0.034 seconds
|Sort by: date | relevance|
[en] Alumina template-synthesized nanostructure materials have unique properties which are very attractive and have been under intensive research in recent years. We describe the latest developments in the preparation of one-dimensional magnetic nanowire arrays by electrodeposition. Many kinds of array structures, such as elemental, alloy, multilayer and superlattice nanowires, are reviewed. Future research directions of super-high density magnetic recording and potential applications of the giant magnetic resistance of magnetic nanowires are also discussed. (authors)
[en] Several works were used metal as background for generating high absorbance due to destructive interference from the superposition of multiple reflections on metamaterial absorber. In this work, we purpose tailoring multiple reflection by using graphene as background for tunable terahertz metamaterial absorber. Graphene’s properties can be adjusted by an applied voltage. The Fermi energy of graphene was adjusted from 0.2 meV till 1 meV in this work. There is around 0.02%–0.14% error between numerical and analytical calculation of absorbance result due to analytical calculation error process. The adjusting graphene’s properties could tailor the superposition of multiple reflections on metamaterial unit cell-graphene layer. (paper)
[en] Highlights: • GO-SiO2 rGO-SiO2 composites were prepared via chemical-thermal method. • HA-SiO2 and tHA-SiO2 composites were obtained by wet chemical techniques. • The morpho-structural characteristics of composites were evaluated and compared. • The rGO-SiO2 and tHA-SiO2 showed the highest antibacterial effect on E. Coli and S. Aureus.
[en] Graphene, a one-atom-thick sheet of carbon atoms, is a material that is attracting hot interest in condensed matter physics. The properties of graphene are highly sensitive to atomic structure and surface morphology, so the structure is of basic importance. In this paper we will review transmission electron microscopy (TEM) studies on graphene's structure, including the layer numbers, stacking, orientation and surface morphology. Studies on the surface defects, atomic edges and adatoms by high-resolution TEM imaging will also be described. (authors)
[en] We show that the optical excitation of multi-valley systems leads to valley currents which depend on the light polarization. The net electric current, determined by the vector sum of single-valley contributions, vanishes for some peculiar distributions of carriers in the valley and momentum spaces forming a pure valley current. We report on the study of this phenomenon, both experimental and theoretical, for graphene and 2D electron channels on the silicon surface
[en] Highlights: • The transition between a fused-ring structure toward its single-ring counterpart is studied. • The change occurs at certain structure instead of a gradual transition. • The fused counterparts can be treated as a modification in the aromatic path of a single ring aromatic motif. • Useful approach to evaluate the formation of defects or larger-rings in graphene motifs. The fused-to-single-ring transition is studied through a 10πe series given the series from naphthalene to annulene. Our results suggest that change occurs at certain structure instead of a gradual transition. In the transition point, given by bicyclo[7.1.0]decapentaene, similar magnetic behavior in comparison to the single ring counterpart is found. The systems can be considered to behave as a whole single aromatic structure where the fused counterparts can be treated as a modification in the aromatic path of a single ring aromatic motif, which can viewed as a useful approach to evaluate the formation of defects or larger-rings in graphene motifs.
[en] Random fluctuations of the shot-noise power in disordered graphene nanoribbons are studied. In particular, we calculate the distribution of the shot noise of nanoribbons with zigzag and armchair edge terminations. We show that the shot noise statistics is different for each type of these two graphene structures, which is a consequence of the presence of different electron localizations: while in zigzag nanoribbons electronic edge states are Anderson localized, in armchair nanoribbons edge states are absent, but electrons are anomalously localized. Our analytical results are verified by tight binding numerical simulations with random hopping elements, i.e., off diagonal disorder, which preserves the symmetry of the graphene sublattices.
[en] Electronic transport properties of out-of-plane graphene nanoribbon intersections have been investigated by using computational method. The inter-distance between two graphene nanoribbons is found to affect the transport properties strongly and its affection can be neglected for larger ones, even under an external bias. Wider graphene nanoribbons will bring stronger interaction into the system, and result in more transmission dips. Moreover, the stacking configuration between two graphene nanoribbons is found to be crucial for the electronic transport under an external bias, as it can affect the electronic transport strongly near the charge neutral point. -- Highlights: ► Transport properties of out-of-plane GNR intersections which constructs from one zigzag GNR and one armchair GNR were studied. ► The effect of the inter-distance, an external bias and the stacking types on the transport properties has been studied. ► The inter-distance is found to affect the transport properties strongly, even under an external bias. ► The stacking configuration between the two GNRs is found to be crucial for the electronic transport under external bias.
[en] Graphene is intrinsically ultra-stiff in its plane. Its huge mechanical mismatch when interfacing with ultra-compliant biological tissues and elastomers (7–9 orders of magnitude difference in stiffness) poses significant challenge in its application to functional devices such as epidermal electronics and sensing prosthesis. We offer a feasible and promising solution to this significant challenge by suitably patterning graphene into a nanomesh. Through systematic coarse-grained simulations, we show that graphene nanomesh can be made extremely compliant with nearly zero stiffness up to about 20% elongation and then remain highly compliant up to about 50% elongation