Complete light absorption in graphene-metamaterial corrugated structures

We show that surface-plasmon polaritons excited in negative permittivity metamaterials having shallow periodic surface corrugation profiles can be explored to push the absorption of single and continuous sheets of graphene up to 100%. In the relaxation regime, the position of the plasmonic resonances of the hybrid system is determined by the plasma frequency of the metamaterial, allowing the frequency range for enhanced absorption to be set without the need of engineering graphene.Comment: 6 pages, 4 figures; published version: text revised and references adde

A novel framework for the use of workflow system in the integration of supply chain tiers

The global competition has imposed challenges to supply chain integration, mainly, during the process of obtain information to make demand management decisions. This paper proposes an integrated framework for data collection, analysis and results dissemination in the supply chain management (SCM), contributing to research and alternatives for \u201cThe Bullwhip Effect\u201d issue. In this sense, it is necessary to discuss the integration of supply chain management, Enterprise Resources Planning (ERP) functionality and others systems, to enlarge this scope to the total supply chain players. The ERP web-based tool and Workflow Systems (WS) can contribute to solve issues related to supply chain management. Starting from a detailed analysis of the research background regarding current SCM definitions and integration problems, Information Technology and Communication (ITC) development and WS in order to map and ensure flow fluency; the paper proposes a model to increase the overall integrations and an application in a case study for supporting the decisions that are aligned with the company\u2019s strategic objectives. This paper is divided in: research background; proposed model of the SC integration; case study, conclusions and future research

Confined magneto-optical waves in graphene

The electromagnetic mode spectrum of single-layer graphene subjected to a quantizing magnetic field is computed taking into account intraband and interband contributions to the magneto-optical conductivity. We find that a sequence of weakly decaying quasi-transverse-electric modes, separated by magnetoplasmon polariton modes, emerge due to the quantizing magnetic field. The characteristics of these modes are tuneable, by changing the magnetic field or the Fermi energy.Comment: 9 pages, 7 figures. published version: text and figures revised and updated + new references and one figure adde

Strong flavour changing effective operator contributions to single top quark production

We study the effects of dimension six effective operators on the production of single top quarks at the LHC. The operator set considered includes terms with effective gluon interactions and four-fermion terms. Analytic expressions for the several partonic cross sections of single top production will be presented, as well as the results of their integration on the parton density functions.Comment: 20 pages, 7 fig

Exchange coupling between magnetic layers across non-magnetic superlattices

The oscillation periods of the interlayer exchange coupling are investigated when two magnetic layers are separated by a metallic superlattice of two distinct non-magnetic materials. In spite of the conventional behaviour of the coupling as a function of the spacer thickness, new periods arise when the coupling is looked upon as a function of the number of cells of the superlattice. The new periodicity results from the deformation of the corresponding Fermi surface, which is explicitly related to a few controllable parameters, allowing the oscillation periods to be tuned.Comment: 13 pages; 5 figures; To appear in J. Phys.: Cond. Matte

The split-operator technique for the study of spinorial wavepacket dynamics

The split-operator technique for wave packet propagation in quantum systems is expanded here to the case of propagating wave functions describing Schr\"odinger particles, namely, charge carriers in semiconductor nanostructures within the effective mass approximation, in the presence of Zeeman effect, as well as of Rashba and Dresselhaus spin-orbit interactions. We also demonstrate that simple modifications to the expanded technique allow us to calculate the time evolution of wave packets describing Dirac particles, which are relevant for the study of transport properties in graphene.Comment: 19 pages, 4 figure