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تسجيل مستخدم جديدMolecular sensor based on graphene nanoribbons
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In this work we study thermoelectric properties of graphene nanoribbons with side-attached organic molecules. By adopting a single-band tight binding Hamiltonian and the Greens function formalism, we calculated the transmission and Seebeck coefficients for different hybrid systems. The corresponding thermopower profiles exhibit a series of sharp peaks at the eigenenergies of the isolated molecule. We study the effects of the temperature on the thermoelectric response, and we consider random configurations of molecule distributions, in different disorder regimes. The main characteristics of the thermopower are not destroyed under temperature and disorder, indicating the robustness of the system as a proposed molecular thermo-sensor device.
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Based on first-principles calculations we predict that periodically repeated junctions of armchair graphene nanoribbons of different widths form superlattice structures. In these superlattice heterostructures the width and the energy gap are modulate
d in real space and specific states are confined in certain segments. Orientation of constituent nanoribbons, their width and length, the symmetry of the junction are the structural parameters to engineer electronic properties of these quantum structures. Not only the size modulation, but also composition modulation, such as periodically repeated, commensurate heterojunctions of BN and graphene honeycomb nanoribbons result in a multiple quantum well structure. We showed that these graphene based quantum structures can introduce novel concepts to design nanodevices.
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atic fields to enhance gas-plasmon interactions and to increase plasmon sensing ability. We discuss the relative strengths of these trapping forces and found gas adsorption in a typical nanoribbon array plasmonic setup produces measurable dips in optical extinction of magnitude 0.1 % for gas concentration of about parts per thousand level.
We study the conductance through two types of graphene nanostructures: nanoribbon junctions in which the width changes from wide to narrow, and curved nanoribbons. In the wide-narrow structures, substantial reflection occurs from the wide-narrow inte
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In this study, we examine the mechanism of nanopore-based DNA sequencing using a voltage bias across a graphene nanoribbon. Using density functional theory and a non-equilibrium Greens function approach, we determine the transmission spectra and curr
ent profile for adenine, guanine, cytosine, thymine, and uracil as a function of bias voltage in an energy minimized configuration. Utilizing the transmission current, we provide a general methodology for the development of a three nanopore graphene-based device that can be used to distinguish between the various nucleobases for DNA/RNA sequencing. From our analysis, we deduce that it is possible to use different transverse currents across a multi-nanopore device to differentiate between nucleobases using various voltages of 0.5, 1.3, and 1.6 V. Overall, our goal is to improve nanopore design to further DNA/RNA nucleobase sequencing and biomolecule identification techniques.
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