By Topic

Nanotechnology, 2002. IEEE-NANO 2002. Proceedings of the 2002 2nd IEEE Conference on

Date 28-28 Aug. 2002

Filter Results

Displaying Results 1 - 25 of 119
  • Proceedings of the 2002 2nd IEEE Conference on Nanotechnology (Cat. No.02TH8630)

    Publication Year: 2002
    Save to Project icon | Request Permissions | PDF file iconPDF (912 KB)  
    Freely Available from IEEE
  • Tbit/inch/sup 2/ ferroelectric data storage using scanning nonlinear dielectric microscopy

    Publication Year: 2002 , Page(s): 255 - 259
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (263 KB) |  | HTML iconHTML  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • II-VI semiconductor nanoparticles formed by Langmuir-Blodgett film technique: optical study

    Publication Year: 2002 , Page(s): 261 - 264
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (263 KB) |  | HTML iconHTML  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Atomic interdiffusion for integration of quantum dot optoelectronic devices

    Publication Year: 2002 , Page(s): 337 - 340
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (275 KB) |  | HTML iconHTML  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-fidelity modeling of nanosystems: novel methods and paradigms

    Publication Year: 2002 , Page(s): 93 - 97
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (310 KB) |  | HTML iconHTML  

    Recent scientific and technological developments have stimulated basic, applied, and experimental research in nanoengineering, nanoscience, and nanotechnology advancing fundamental paradigms. Contemporary results in nonlinear quantum electromagnetics and mechanics, advances in modeling and simulation of complex nanosystems, bio-mimicking and prototyping, discovery of new phenomena and effects, as well as rapid engineering/technological advances in fabrication (molecular wires, carbon nanotubes, thin films, et cetera), provide enabling benefits and capabilities to devise and fabricate new nanostructures, nanodevices, and nanoelectromechanical systems (NEMS). Critical problems that remain to be addressed and solved are the fundamental research to model, simulate, and analyze NEMS. High-fidelity modeling, heterogeneous simulation and data-intensive analysis must be performed. Using the developed paradigms, we examine these problems for NEMS and report the promising solution of the Schrodinger equation using the optimality principle. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Nano-scale optical and quantum optical devices based on photonic crystals

    Publication Year: 2002 , Page(s): 319 - 321
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (308 KB) |  | HTML iconHTML  

    We review our theoretical and experimental work on functional optical devices based on planar photonic crystals. Beside standard photonic applications, these structures can also be used as building blocks of quantum networks. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Nanotechnologies and nanosystems of informatics as a basis for self-replication

    Publication Year: 2002 , Page(s): 99 - 102
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (309 KB) |  | HTML iconHTML  

    If basic elements applied in given technology are single atoms or molecules, then this technology is named nanotechnology. If basic elements of codes used in the given system of informatics are single atoms or molecules, then such a system of informatics is called nanosystem of informatics. Recent research on the nanotechnological processes of molecular products and objects synthesis as well as research on the nanosystems of informatics stimulate development of the technical systems of informatics. Until now, the latter have been used mainly for the computational tasks, when similarly to biological organisms, they allowed for development of self-replicating products and complete objects. One can focus here on the model of a circulation of materials, information and energy in a biological cell, and a model of the self-replication phenomenon. In the model of materials, information and energy circulation, we may distinguish a two-stage process of creating products, which are later on used for objects construction. The first stage is a translation process based on information from mRNA, while the second stage is a phase of post-translational modifications based on environment interaction. The self-replication model presented in this paper refers to a self-replication of a material object together with its internal software, which had determined object's creation. Presented models of materials, information and energy circulation in a biological cell together with models of self-replication phenomenon can be the basis for a design and development of the technical systems of informatics capable to create the self-replicating products and objects. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Gene expression modelling with the use of Boolean network and artificial neural network

    Publication Year: 2002 , Page(s): 157 - 160
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (396 KB) |  | HTML iconHTML  

    Recent progress in molecular biology has enabled exploration of the mechanisms of genetic information processing in organisms. With the use of new technologies it is possible to observe a state of the cell at different time steps, assemble and disassemble genetic information carriers, etc. With new tools available there is a chance to answer the question that has motivated our predecessors. There is a chance to find out "how it all works?" In this paper we study a method of gene networks modelling. A gene network is a mass of genes interacting with one another through expression. The model is used to infer a gene expression mechanism on the basis of gene expression measurements. In our approach we employed two network models: a Boolean network model and an artificial neural network model. We have shown that large data can be handled efficiently with the aid of already developed methods and algorithms. Thanks to them, drawing meaningful inferences from large gene expression data may be converted into simple tasks. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Photovoltage spectroscopy and electroluminescence of ZnSe/CdxZn1-xSe superlattices

    Publication Year: 2002 , Page(s): 185 - 187
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (247 KB) |  | HTML iconHTML  

    The ZnSe/CdxZn1-xSe superlattices with non-doping layers, grown by molecular beam epitaxy, were investigated by electroluminescence and photovoltage spectroscopy. Green-blue electroluminescence from the quantum wells has been observed at 77 K and 293 K. Well-resolved peaks attributed to excitonic absorption, as well as photosensitivity bands corresponding to the CdxZn1-xSe/ZnSe superlattice region and the ZnSe buffer layer, have been observed in photovoltaic measurements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Selective growth of ZnO nanotips using MOCVD

    Publication Year: 2002 , Page(s): 21 - 24
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (402 KB) |  | HTML iconHTML  

    ZnO is a wide bandgap semiconductor having a direct bandgap of 3.32 eV at room temperature. It has an exciton binding energy of 60 meV. It is found to be significantly more radiation hard than Si, GaAs, and GaN, which is critical against wearing out during field emission. Furthermore, ZnO can also be made as transparent and highly conductive, or piezoelectric. The ZnO nanotips can be grown at relatively low temperatures, giving ZnO a unique advantage over other wide bandgap semiconductors, such as GaN and SiC. In the present work, we report the selective growth of ZnO nanotips on various substrates using MOCVD. The ZnO nanotips are single crystalline, n-type conductive and show good optical properties. These nanotips have potential applications in field emission devices and UV photonics. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Coherent LO phonons generated by high-velocity electrons in two-dimensional channels and their impact on carrier transport

    Publication Year: 2002 , Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (329 KB) |  | HTML iconHTML  

    We show that Cerenkov generation of confined LO phonons by drifting electrons can be achieved in biased quantum wells (QWs). Both linear and nonlinear regimes of phonon generation are analyzed. The kinetic parameters of the drifting electrons are estimated by using momentum and energy balance equations for electron scattering by the confined optical phonons. Our findings suggest that high efficiency electrical generation of coherent optical phonons can be realized in two-dimensional structures with high drift velocities, such as AlAs/GaAs/AlAs and GaSb/InSb/GaSb QWs. Due to high conversion efficiency, the effect of current driven phonon generation can be an important mechanism of current suppression in two-dimensional channels where its contribution to saturation of current-voltage characteristics can compete with the contribution of intervalley transitions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Large pure refractive nonlinearity of nanostructure silica aerogel at near infrared wavelength

    Publication Year: 2002 , Page(s): 495 - 497
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB) |  | HTML iconHTML  

    The nonlinear refraction coefficient of the third-order susceptibility of silica aerogel was estimated to be ∼-1.5×10-15 m2/W (∼-3.67×10-9 esu) by a signal-beam z-scan technique with ∼1 ps Ti:sapphire lasers. The third-order nonlinear refraction coefficient of nanostructure silica aerogel is almost five orders larger than the nonlinear (χ3) refraction of bulk material. The large nonlinear refraction originates mainly from the direct excitation to the surface trapped states, and the one-photon resonance process. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • CdS nanoparticles embedded in metal-insulator-semiconductor structures

    Publication Year: 2002 , Page(s): 265 - 268
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (297 KB) |  | HTML iconHTML  

    Metal-insulator-semiconductor structures were fabricated using 40 layers thick Langmuir-Blodgett (LB) films of stearic acid (SA) on hydrophobic n-type silicon (n-Si) substrates. Samples containing cadmium sulphide (CdS) nanoparticles exhibit higher rectification than untreated ones by two orders of magnitudes. The flat band voltage was found to be 0.5 V from the capacitance measurement. The effective dielectric constant of the CdS embedded SA matrix was estimated to be 5.2. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effect of network topology on nanocluster film transport

    Publication Year: 2002 , Page(s): 239 - 242
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (309 KB)  

    The effects of network topology on electron transport is studied using Monte Carlo simulations of tunnel junction networks with transport governed by Coulomb blockade. Both the threshold voltage shift and the nonlinearity of the I-V curves are sensitive to lateral fluctuations of the conduction paths due to random voids. The nonlinearity is found to be maximized for aspect ratios of the network of unity or larger and for random void networks with 50% horizontal connections. Comparisons are made with Au nanocluster I-V measurements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Balancing QCA logic gates under image charge neutralization

    Publication Year: 2002 , Page(s): 347 - 350
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (321 KB) |  | HTML iconHTML  

    Quantum-dot cellular automata (QCA) devices for computing through energy relaxation via quantum mechanical effects, promise high speed, very low power, and extremely high density. Steady progress has been made in implementing QCA; a small binary logic device has recently been manufactured and its logical switching behavior demonstrated. However, computation with hierarchical assemblies of primitive logic devices has not yet been demonstrated. Earlier work has shown that the four ground states of the originally proposed automata for implementing AND and OR are at slightly different energy levels. Because of this, certain combinations of these gates relax to ground states that encode an incorrect computation. A previously proposed construct, which essentially computes all four ground states simultaneously and thus evens out the disparities, works well under the idealized charge neutralization scheme originally proposed by the inventors of QCA. Unfortunately, under the more realistic image charge neutralization, the construction has only slightly better characteristics than the original gates and only then when the separation distance between the automaton and the metal layer generating the image charges is rather small. This paper investigates methods for evening out the disparate ground states in the presence of image charge neutralization. Previously, it was shown that the more symmetric the automaton, the better its computational behavior under image charge neutralization. It is shown that adding symmetry also reduces the disparity in ground states and a new construct for balancing QCA logic gates is presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Assembly of electrospun nanofibers into crossbars

    Publication Year: 2002 , Page(s): 283 - 286
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (390 KB) |  | HTML iconHTML  

    We report an approach for the hierarchical assembly of nanofibers into crossbar nanostructures. The polymer nanofibers are created through electrospinning process with diameters ranging in 10-80 nm and lengths of up to centimeters. By controlling the electrostatic field and the polymer rheology of the nanofibers, they can be assembled into parallel periodic arrays. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Impact of airborne molecular contamination to nano-device performance

    Publication Year: 2002 , Page(s): 461 - 464
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (359 KB) |  | HTML iconHTML  

    In this paper, we detected most airborne molecular contamination (AMC) in our present cleanroom and in our specially equipped clean bench through air sampling and wafer sampling experiments. We then investigate the effects of AMC on device performance under different filter modules. We discovered that the NEUROFINE PTFE filter combined with the chemical filters has excellent controlling ability for metal, organic and inorganic contaminations. We believe that the novel filter combination can be used to further improve the device manufacturing environment when the device is continuously scaled down to nanometer generation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On Ladders' complexity mechanism and quantitative regulation of scalable molecular computers by Rho family GTPases

    Publication Year: 2002 , Page(s): 329 - 332
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (398 KB) |  | HTML iconHTML  

    We propose a new bio-molecular computing method based on Rho family GTPases, and report that the Ladders' complexity increasing phenomenon is observed when molecular computing by Rho family GTPases is applied to solve large-scale 3-SAT problems. We also present the optimal condition for the regulation scheme as Pg=h Pl/Ql where Pg is the probability of global communication among the sub-pathways, Pl is the probability of local communication in the sub-pathways within the domain of the neighborhood, and h is the experimental coefficient dependent on the temperature, kinase activity and sorts of cells. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Discovery and classification of motion nanodevices

    Publication Year: 2002 , Page(s): 471 - 476
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (505 KB) |  | HTML iconHTML  

    Enabling technologies have been developed to synthesize and fabricate organic, inorganic and hybrid nanostructures. The fundamental theory has been further expanded to design, model, simulate and analyze simple nanoelectromechanical systems and devices. There are distinguishing features between nanoscale electromechanical systems, devices, and structures. In general, systems integrate nanodevices and nanostructures. However, using commonly used and accepted notations, we assume that the motion nanodevice is a nanoelectromechanical system (NEMS). A spectrum of fundamental problems primarily associated with devising and discovering novel NEMS remains. These nanodevices can be classified as electronic and motion (rotational and translational transducers - actuators and sensors) nanoscale devices. This paper concentrates on the motion nanodevices. The key focus areas are synthesis, classification and analysis. We emphasize classification and synthesis paradigms with ultimate goal of classifying existing and discovering novel NEMS by performing electromagnetic-geometry synthesis. It is illustrated that NEMS intelligent databases can be developed within evolutionary-based CAD. The synthesis and classification paradigm reported directly leverages fundamental physics laws and high-fidelity modeling, allowing the designer to attain physical and behavioral (steady-state and transient) data-intensive analysis, heterogeneous simulation, optimization, performance assessment, outcome prediction, etc. We focus our attention on rotational and translational nanodevices which can be controlled by driving/sensing controlling/processing nanoelectronics. The examined nanodevices can be considered as NEMS as the electromagnetic-based nanomachines integrate motion and radiating energy nanodevices as well as nanostructures. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Nano-sized pore formation in p-type silicon for automotive applications

    Publication Year: 2002 , Page(s): 457 - 460
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (473 KB) |  | HTML iconHTML  

    Self-organized electrochemical etching of p-type silicon (Si) has been used to study random micropore formation which produces porous Si structures with nanometer well thickness. The density of micropores, i.e. the porosity, can be varied in a wide range by choice of the substrate doping level. Surface enlargement up to a factor of 10000 and more can be easily achieved by choice of appropriate conditions in the anodic etch process. In addition, we demonstrate deep anodic etching (DAE) of a pinhole array in Si by lithographic pre-patterning and subsequent etch using potassium hydroxide (KOH). The Si wafer is then anodically etched which produces deep channels, thus creating porous structures with enlarged surface. Such channels have large application potential as a carrier structure for the catalyst in micro-steam fuel reformers in compact fuel cells used as auxiliary power units for the on-board electronics in vehicles or can be used for fuel injection or fuel heating systems. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An RF circuit model for carbon nanotubes

    Publication Year: 2002 , Page(s): 393 - 396
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB) |  | HTML iconHTML  

    We develop an rf circuit model for single walled carbon nanotubes for both dc and capacitively contacted geometries. By modeling the nanotube as a nano-transmission line with distributed kinetic and magnetic inductance as well as distributed quantum and electrostatic capacitance, we calculate the complex, frequency dependent impedance for a variety of measurement geometries. Exciting voltage waves on the nano-transmission line is equivalent to directly exciting the yet-to-be observed one dimensional plasmons, the low energy excitation of a Luttinger liquid. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Brownian motor analysis and its application to nanosystems

    Publication Year: 2002 , Page(s): 151 - 155
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (322 KB) |  | HTML iconHTML  

    On the molecular scale biological machines of the size approximately 0.01 μm perform transport guaranteeing functionality of living cells. Thermal and quantum fluctuations are the major source of energy for such minuscule machines. They transport biological materials and ions, build proteins, attain motility of the cell, etc. Fluctuation-driven transport, mapped by the Brownian ratchet principle, gives us the understanding of how electrochemical energy is converted into mechanical energy. The importance of Brownian motion is its versatility in explaining a wide range of biological processes that occur at the molecular level. This paper reports model developments, simulation, and analysis of different mechanisms in nanobiomotors. One example is kinesin, a protein molecule that is in motion along microtubules in living cells and transports material. Another example is myosin which is active when a muscle contracts. The force generation is a topic of current research. How do molecular motors behave in a noisy environment? One model suggests that the motors use the random Brownian motion to do work. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical disk mastering using an electron beam recorder

    Publication Year: 2002 , Page(s): 169 - 172
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (303 KB) |  | HTML iconHTML  

    For the next-generation optical disk, electron beam mastering has been considered as a technique with high potential. Parameters of exposure and development processes, such as focus distance, beam current, linear velocity, and development time, have been discussed in our previous paper (2001). However, for electron beam mastering, electron backscattering is also an important problem. In this paper, we discussed how the proximity effect caused by backscattered electrons influences the exposure linewidth (FWHM) and the thickness of residual resist as track pitch decreases. We attacked this problem by raising beam voltage and changing the material of a substrate. According to experimental results, depositing a SiO2 film or a Si3N4 film on a substrate can partially solve this problem. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Aharonov-Bohm flux control of transport and microwave energy absorption in a parallel double-dot system

    Publication Year: 2002 , Page(s): 295 - 300
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (390 KB) |  | HTML iconHTML  

    We analyze a tunnel-coupled double-dot structure in a parallel arrangement between leads in the presence of magnetic flux to determine its charge transport and microwave absorption properties. Nonequilibrium. Green's function methods are employed (taking account of dot-lead tunnel coupling, electron-phonon interaction and inter-dot Coulomb repulsion) to calculate the energies, populations and linewidths of the bonding and antibonding states in the double-dot structure for various values of magnetic flux threading the structure. We find that there are resonant values of the Aharonov-Bohm magnetic flux, for which one of these states is disconnected from the leads by phase and there is only one step in the current-voltage characteristics. For non-resonant fluxes there are either two steps or one sharp step depending on the common equilibrium chemical potential of the leads. In the case of two steps, the current value in the plateau region between the steps is an oscillatory function of the applied magnetic flux. In the present work, we also analyze microwave energy absorption. At a resonant flux, when one of levels is disconnected, there is residual absorption of the external microwave energy even at high applied bias. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Imaging properties of a metamaterial superlens

    Publication Year: 2002 , Page(s): 225 - 228
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (318 KB) |  | HTML iconHTML  

    The subwavelength imaging quality of a metamaterial superlens is studied numerically in the wavevector domain. Examples of image compression and magnification are given and resolution limits are discussed. A minimal resolution of λ/6 is obtained using a 36 nm silver film at 364 nm wavelength. The simulation also demonstrates the power flux is no longer a good measure to determine the focal plane of a superlens due the elevated field strength at the exit side of the metamaterial slab. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.