Graphene has attracted considerable attention as a next-generation transparent conducting electrode, because of its high electrical conductivity and optical transparency. Various optoelectronic devices comprising graphene as a bottom electrode, such as organic light-emitting diodes (OLEDs), organic photovoltaics, quantum-dot LEDs, and light-emitting electrochemical cells, have recently been rep...

In this paper, research has been carried out on the electronic properties of nanostructured graphene. We focus our attention trapped states proposed systems such as spherical and toroidal graphene quantum dots (GQDs). Using a continuum model, by solving Dirac-Weyl equation, applying periodic boundary conditions two types, i.e., either with zigzag edges only or both armchair edges, we obtain ana...

in order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. to do this we have investigated optical waveguide both with and without optical pumping. the rate of absorption and emission using an array of algaas/gaas quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. by con...

while the application of optical and photonic technologies in the communications, computing, medicine and industrial manufacturing has been growing rapidly, the miniaturization of these technologies has been slow due to the limitation on the diffraction. however, the developments of nanoscale components and guiding methods are continuing with a rapid pace. since waveguiding is a fundamental iss...

in this report, we present a facile approach for the synthesis of luminescent cds and cds:mn+2 nanocrystals by reaction of cdso4 and na2s2o3 in the presence of thioglycerol (c3h8o2s) as capping agent. the influence of various experimental variables including, ph values and percentage of dopant, on the growth rate and optical properties of the obtained cds nanocrystals has been systematically in...

colloidal quantum dots offer broad tuning of semiconductor band structure via the quantum size effect. in this paper, we present a detailed investigation on the influence of the thickness of colloidal lead sulfide (pbs) nanocrystals (active layer) to the photovoltaic performance of colloidal quantum dot solar cells. the pbs nanocrystals (qds) were synthesized in a non-coordinating solvent, 1-oc...

quantum-dot cellular automata (qca) has low power consumption and high density and regularity. qca widely supports the new devices designed for nanotechnology. application of qca technology as an alternative method for cmos technology on nano-scale shows a promising future. this paper presents successful designing, layout and analysis of multiplexer with a new structure in qca technique. in thi...

the full adders (fas) constitute the essential elements of digital systems, in a sense that they affect the circuit parameters of such systems. with respect to the mosfet restrictions, its replacement by new devices and technologies is inevitable. qca is one of the accomplishments in nanotechnology nominated as the candidate for mosfet replacement. in this article 4 new layouts are presented fo...

We demonstrate dispersive readout of individual charge states in a gate-defined few-electron quantum dot bilayer graphene. employ radio frequency reflectometry circuit, where an LC resonator with resonance close to 280 MHz is directly coupled Ohmic contact the device. The detection scheme based on changes capacitance operates over wide gate-voltage range and allows us probe excited down single-...

We study theoretically Coulomb drag in capacitively coupled quantum dots (CQDs)-a bias-driven dot coupled to an unbiased dot where transport is due to Coulomb mediated energy transfer drag. To this end, we introduce a master-equation approach that accounts for higher-order tunneling (cotunneling) processes as well as energy-dependent lead couplings, and identify a mesoscopic Coulomb drag mechan...