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2013

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Articles 121 - 150 of 223

Full-Text Articles in Nanoscience and Nanotechnology

Thermoreflectance Imaging Of Sub 100 Ns Pulsed Cooling In High-Speed Thermoelectric Microcoolers, Bjorn Vermeersch, Je-Hyeong Bahk, James Christofferson, Ali Shakouri Mar 2013

Thermoreflectance Imaging Of Sub 100 Ns Pulsed Cooling In High-Speed Thermoelectric Microcoolers, Bjorn Vermeersch, Je-Hyeong Bahk, James Christofferson, Ali Shakouri

Birck and NCN Publications

Miniaturized thin film thermoelectric coolers have received considerable attention as potential means to locally address hot spots in microprocessors. Given the highly dynamic workload in complex integrated circuits, the need arises for a thorough understanding of the high-speed thermal behavior of microcoolers. Although some prior work on transient Peltier cooling in pulsed operation is available, these studies mostly focus on theoretical modeling and typically deal with relatively large modules with time constants well into the millisecond range. In this paper, we present an extensive experimental characterization of 30 x 30 mu m(2) high-speed coplanar SiGe superlattice microcoolers subjected to 300 …

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Shape Memory Metamaterials With Tunable Thermo-Mechanical Response Via Hetero-Epitaxial Integration: A Molecular Dynamics Study, Karthik Guda Vishnu, Alejandro Strachan Mar 2013

Shape Memory Metamaterials With Tunable Thermo-Mechanical Response Via Hetero-Epitaxial Integration: A Molecular Dynamics Study, Karthik Guda Vishnu, Alejandro Strachan

Birck and NCN Publications

We show that nanoscale epitaxial superlattices (SLs) can be used to engineer the energy landscape that governs the martensitic transformation in shape memory alloys and tune their thermo-mechanical response. We demonstrate the approach using large-scale molecular dynamics simulations of a SL material consisting of alternate layers of a shape memory Ni-rich NiAl alloy and NiAl B2 alloy. The non-martensitic NiAl alloy was chosen to reduce the energy barrier that separates the martensite and austenite phases of the SL and its incorporation leads to a reduction in the thermal hysteresis of the transition. This is a desirable feature in applications involving …

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Effects Of Forming Gas Anneal On Ultrathin Ingaas Nanowire Metal-Oxide-Semiconductor Field-Effect Transistors, Mengwei Si, Jiangjiang Gu, Xinwei Wang, Jiayi Shao, Xuefei Li, Michael J. Manfra, Roy G. Gordon, Peide D. Ye Mar 2013

Effects Of Forming Gas Anneal On Ultrathin Ingaas Nanowire Metal-Oxide-Semiconductor Field-Effect Transistors, Mengwei Si, Jiangjiang Gu, Xinwei Wang, Jiayi Shao, Xuefei Li, Michael J. Manfra, Roy G. Gordon, Peide D. Ye

Birck and NCN Publications

InGaAs gate-all-around metal-oxide-semiconductor field-effect transistors (MOSFETs) with 6 nm nanowire thickness have been experimentally demonstrated at sub-80 nm channel length. The effects of forming gas anneal (FGA) on the performance of these devices have been systematically studied. The 30min 400 degrees C FGA (4% H-2/96% N-2) is found to improve the quality of the Al2O3/InGaAs interface, resulting in a subthreshold slope reduction over 20mV/dec (from 117mV/dec in average to 93mV/dec). Moreover, the improvement of interface quality also has positive impact on the on-state device performance. A scaling metrics study has been carried out for FGA treated devices with channel lengths …

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Laser Direct Writing Of Silicon Field Effect Transistor Sensors, Woongsik Nam, James I. Mitchell, Chookiat Tansarawiput, Minghao Qi, Xianfan Xu Mar 2013

Laser Direct Writing Of Silicon Field Effect Transistor Sensors, Woongsik Nam, James I. Mitchell, Chookiat Tansarawiput, Minghao Qi, Xianfan Xu

Birck and NCN Publications

We demonstrate a single step technique to fabricate silicon wires for field effect transistor sensors. Boron-doped silicon wires are fabricated using laser direct writing in combination with chemical vapor deposition, which has the advantages of precise control of position, orientation, and length, and in situ doping. The silicon wires can be fabricated to have very rough surfaces by controlling laser operation parameters, and thus, have large surface areas, enabling high sensitivity for sensing. Highly sensitive pH sensing is demonstrated. We expect our method can be expanded to the fabrication of various sensing devices beyond chemical sensors. (C) 2013 American Institute …

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Deuterium Uptake In Magnetic-Fusion Devices With Lithium-Conditioned Carbon Walls, P. S. Krstic, Jean Paul Allain, C. N. Taylor, J. Dadras, S. Maeda, K. Morokuma, J. Jakowski, A. Allouche, C. H. Skinner Mar 2013

Deuterium Uptake In Magnetic-Fusion Devices With Lithium-Conditioned Carbon Walls, P. S. Krstic, Jean Paul Allain, C. N. Taylor, J. Dadras, S. Maeda, K. Morokuma, J. Jakowski, A. Allouche, C. H. Skinner

Birck and NCN Publications

Lithium wall conditioning has lowered hydrogenic recycling and dramatically improved plasma performance in many magnetic-fusion devices. In this Letter, we report quantum-classical atomistic simulations and laboratory experiments that elucidate the roles of lithium and oxygen in the uptake of hydrogen in amorphous carbon. Surprisingly, we show that lithium creates a high oxygen concentration on a carbon surface when bombarded by deuterium. Furthermore, surface oxygen, rather than lithium, plays the key role in trapping hydrogen. DOI: 10.1103/PhysRevLett.110.105001

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Thermal Transport In Sige Superlattice Thin Films And Nanowires: Effects Of Specimen And Periodic Lengths, Keng-Hua Lin, Alejandro Strachan Mar 2013

Thermal Transport In Sige Superlattice Thin Films And Nanowires: Effects Of Specimen And Periodic Lengths, Keng-Hua Lin, Alejandro Strachan

Birck and NCN Publications

We compute the thermal conductivity of superlattice (SL) thin films and nanowires for various SL periods and total specimen lengths using nonequilibrium molecular dynamics. Both types of materials exhibit similar behaviors with respect to SL period but the thermal conductivity of the thin films exhibits a significantly higher sensitivity to the specimen length. Notably, the thermal conductivity of SL thin films is smaller than those of the corresponding nanowires for specimen lengths below approximately 35 nm. These results arise from the complex dependence of the conductivities of the interfaces and the SL components on the specimen size and period. These …

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A Computational Study Of The Thermoelectric Performance Of Ultrathin Bi2te3 Films, Jesse Maassen, Mark S. Lundstrom Mar 2013

A Computational Study Of The Thermoelectric Performance Of Ultrathin Bi2te3 Films, Jesse Maassen, Mark S. Lundstrom

Birck and NCN Publications

The ballistic thermoelectric performance of ultrathin films of Bi2Te3, ranging in thickness from 1 to 6 quintuple layers, is analyzed using density functional theory combined with the Landauer approach. Our results show that the thinnest film, corresponding to a single quintuple layer, has an intrinsic advantage originating from the particular shape of its valence band, leading to a large power factor and figure-of-merit exceeding bulk Bi2Te3. The interaction between the top and bottom topological surface states is key. The thinnest film yields a six-fold increase in power factor compared to bulk. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4794534]

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Study Of The Growth And Switching Kinetics On Ferroelectric Nanocrystals Of Copolymer Vinylidene Fluoride And Trifluoroethylene On An Atomic Force Microscope, R. V. Gaynutdinov, O. A. Lysova, A. L. Tolstikhina, V. M. Fridkin, S. G. Yudin, Stephen Ducharme Mar 2013

Study Of The Growth And Switching Kinetics On Ferroelectric Nanocrystals Of Copolymer Vinylidene Fluoride And Trifluoroethylene On An Atomic Force Microscope, R. V. Gaynutdinov, O. A. Lysova, A. L. Tolstikhina, V. M. Fridkin, S. G. Yudin, Stephen Ducharme

Stephen Ducharme Publications

The growth of nanocrystals obtained from Langmuir-Blodgett films of ferroelectric copolymer consisting of 70% vinylidene fluoride and 30% trifluoroethylene has been investigated by atomic force microscopy (AFM). The radius and concentration of nanocrystals are found to depend on the annealing time of the film. A model for nanocrystal growth is proposed which yields adequate time dependences for nanocrystal size parameters. The switching kinetics of individual ferroelectric nanocrystals with an average diameter of 100–200 nm and a height of 15–20 nm has been investigated in the piezoelectric response mode. It is shown that the switching of nanocrystals has an activation character.

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Limitations Of The High-Low C-V Technique For Mos Interfaces With Large Time Constant Dispersion, Ashish Verma Penumatcha, Steven Swandono, James A. Cooper Mar 2013

Limitations Of The High-Low C-V Technique For Mos Interfaces With Large Time Constant Dispersion, Ashish Verma Penumatcha, Steven Swandono, James A. Cooper

Birck and NCN Publications

We discuss the limitations of the high-low CV technique in evaluating the interface trap density (D-TT) in MOS samples with a large time constant dispersion, as occurs in silicon carbide (SiC). We show that the high-low technique can seriously underestimate D-IT for samples with large time constant dispersion, even if elevated temperatures are used to extend the range of validity.

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Combination And Applications Of Time-Resolved Surface Plasmon Resonance Spectroscopy And Electrochemical Methods, Yu Bao, Yan Mao, Wei Wang, Zheng-Gang Li, Li Niu Feb 2013

Combination And Applications Of Time-Resolved Surface Plasmon Resonance Spectroscopy And Electrochemical Methods, Yu Bao, Yan Mao, Wei Wang, Zheng-Gang Li, Li Niu

Journal of Electrochemistry

Electrochemical-surface plasmon resonance (EC-SPR) technique, developed in recent years, is a new technology which combines time-resolved surface plasmon resonance spectroscopy and electrochemical methods. Surface plasmon resonance (SPR) is a physical phenomenon generated by optical coupling using a metallic thin film and is very sensitive to optical analysis. The principles of SPR and EC-SPR are briefly introduced and the applications of the combination of SPR spectroscopy with electrochemical techniques are reviewed in this paper. This new technology has been widely used in such research areas as reaction dynamics, biochemical sensors, electrode/electrolyte interfaces, kinetic parameters and bimolecular interactions.

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An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2C/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen Feb 2013

An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2C/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen

Journal of Electrochemistry

A 40% Pt on Mo2C/GC catalyst has been prepared by ion exchange method. The mechanism of methanol electrooxidation on Pt-Mo2C/GC and commercial Pt/C catalysts in acidic media was studied by cyclic voltammetry, XRD measurements and in-situ Fourier transform infrared spectroelectrochemistry. The results revealed that the Pt nanoparticles were uniformly dispersed on Mo2C/GC with an average particle size of 3 nm. The cyclic voltammetric and chronopotentiometric experiments indicated that Pt-Mo2C/GC catalyst exhibited a better performance for methanol oxidation than that of Pt/C in acid solution. A negative shift over 90 mV of the …

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Applications Of Ellipsometry In The Investigations Of Electrode-Solution Interface, Jing-Lei Lei, Liang-Liu Wu, Ling-Jie Li, Sheng-Mao Wu, Sheng-Tao Zhang Feb 2013

Applications Of Ellipsometry In The Investigations Of Electrode-Solution Interface, Jing-Lei Lei, Liang-Liu Wu, Ling-Jie Li, Sheng-Mao Wu, Sheng-Tao Zhang

Journal of Electrochemistry

Ellipsometry is an optical technique with high-sensitivity to quantitatively obtain surface/interface properties such as thickness andrefractive index by analyzing the changes in polarized light reflected from the surface/interface. Its noncontacting and nondestructivenature makes it possible to acquire thein situreal-time information of the change at the surface/interface. Therefore, ellipsometry has been used widely in the electrochemical investigations. In this paper, based on the brief introduction of the measurementprinciple of ellipsometry, the current progress and the future trends of ellipsometry in electrochemistry arediscussed. The applications of ellipsometry in the fields of conversion and storage of electrochemical energy, electrochemistry ofmaterials science,electroanalysisand bioelectrochemistry are …

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Sodium Carbonate Catalyzed Photoelectrochemical Water Splitting Over Tio2 Nanotubes Photoanode, De-Sheng Kong, Jing Wang, Xue-Di Zhang, Xi Zhao, Chao Wang, Yuan-Yuan Feng, Wen-Juan Li Feb 2013

Sodium Carbonate Catalyzed Photoelectrochemical Water Splitting Over Tio2 Nanotubes Photoanode, De-Sheng Kong, Jing Wang, Xue-Di Zhang, Xi Zhao, Chao Wang, Yuan-Yuan Feng, Wen-Juan Li

Journal of Electrochemistry

Surface recombination of the photogenerated electron-hole pairs at semiconductor/electrolyte interface is one of the most essential reasons responsible for lowering photoconversion efficiency (Φ) of light to chemical energy for photoelectrochemical (PEC) water splitting reaction. In this paper, the catalytic effect of sodium carbonate on the oxygen evolution reaction (OER) over TiO2 nanotubes photoanode during PEC water splitting was investigated by performing photocurrent and ac impedance measurements. It was demonstrated that the addiction of 1 mmol•L-1 Na2CO3 in 0.5 mol•L-1 NaClO4 electrolyte can effectively improve the charge transfer properties for the photogenerated holes across …

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High-Resolution Dynamic Atomic Force Microscopy In Liquids With Different Feedback Architectures, John Melcher, David Martinez-Martin, Miriam Jaafar, Julio Gomez-Herrero, Arvind Raman Feb 2013

High-Resolution Dynamic Atomic Force Microscopy In Liquids With Different Feedback Architectures, John Melcher, David Martinez-Martin, Miriam Jaafar, Julio Gomez-Herrero, Arvind Raman

Birck and NCN Publications

The recent achievement of atomic resolution with dynamic atomic force microscopy (dAFM) [Fukuma et al., Appl. Phys. Lett. 2005, 87, 034101], where quality factors of the oscillating probe are inherently low, challenges some accepted beliefs concerning sensitivity and resolution in dAFM imaging modes. Through analysis and experiment we study the performance metrics for high-resolution imaging with dAFM in liquid media with amplitude modulation (AM), frequency modulation (FM) and drive-amplitude modulation (DAM) imaging modes. We find that while the quality factors of dAFM probes may deviate by several orders of magnitude between vacuum and liquid media, their sensitivity to tip-sample forces …

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Cross-Plane Thermal Properties Of Transition Metal Dichalcogenides, C. Muratore, V. Varshney, J. J. Gengler, J. J. Hu, J. E. Bultman, T. M. Smith, P. J. Shamberger, Bo Qiu, Xiulin Ruan, A. K. Roy, A. A. Voevodin Feb 2013

Cross-Plane Thermal Properties Of Transition Metal Dichalcogenides, C. Muratore, V. Varshney, J. J. Gengler, J. J. Hu, J. E. Bultman, T. M. Smith, P. J. Shamberger, Bo Qiu, Xiulin Ruan, A. K. Roy, A. A. Voevodin

Birck and NCN Publications

In this work, we explore the thermal properties of hexagonal transition metal dichalcogenide compounds with different average atomic masses but equivalent microstructures. Thermal conductivity values of sputtered thin films were compared to bulk crystals. The comparison revealed a > 10 fold reduction in thin film thermal conductivity. Structural analysis of the films revealed a turbostratic structure with domain sizes on the order of 5-10 nm. Estimates of phonon scattering lengths at domain boundaries based on computationally derived group velocities were consistent with the observed film microstructure, and accounted for the reduction in thermal conductivity compared to values for bulk crystals. (C) …

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Interfacial Thermal Conductance Limit And Thermal Rectification Across Vertical Carbon Nanotube/Graphene Nanoribbon-Silicon Interfaces, Ajit K. Vallabhaneni, Bo Qiu, Jiuning Hu, Yong P. Chen, Ajit K. Roy, Xiulin Ruan Feb 2013

Interfacial Thermal Conductance Limit And Thermal Rectification Across Vertical Carbon Nanotube/Graphene Nanoribbon-Silicon Interfaces, Ajit K. Vallabhaneni, Bo Qiu, Jiuning Hu, Yong P. Chen, Ajit K. Roy, Xiulin Ruan

Birck and NCN Publications

Various models were previously used to predict interfacial thermal conductance of vertical carbon nanotube (CNT)-silicon interfaces, but the predicted values were several orders of magnitude off the experimental data. In this work, we show that the CNT filling fraction (the ratio of contact area to the surface area of the substrate) is the key to remedy this discrepancy. Using molecular dynamics, we have identified an upper limit of thermal interface conductance for C-Si interface which is around 1.25GW/m(2)K, corresponding to a 100% filling fraction of carbon nanotube or graphene nanoribbon on substrate. By extrapolating to low filling fraction (similar to …

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Unidirectional Spaser In Symmetry-Broken Plasmonic Core-Shell Nanocavity, Xiangeng Meng, Urcan Guler, Alexander V. Kildishev, Koji Fujita, Katsuhisa Tanaka, Vladimir M. Shalaev Feb 2013

Unidirectional Spaser In Symmetry-Broken Plasmonic Core-Shell Nanocavity, Xiangeng Meng, Urcan Guler, Alexander V. Kildishev, Koji Fujita, Katsuhisa Tanaka, Vladimir M. Shalaev

Birck and NCN Publications

The spaser, a quantum amplifier of surface plasmons by stimulated emission of radiation, is recognized as a coherent light source capable of confining optical fields at subwavelength scale. The control over the directionality of spasing has not been addressed so far, especially for a single-particle spasing nanocavity where optical feedback is solely provided by a plasmon resonance. In this work we numerically examine an asymmetric spaser - a resonant system comprising a dielectric core capped by a metal semishell. The proposed spaser emits unidirectionally along the axis of the semishell; this directionality depends neither on the incident polarization nor on …

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Strong Heavy-To-Light Hole Intersubband Absorption In The Valence Band Of Carbon-Doped Gaas/Alas Superlattices, M. I. Hossain, Z. Ikonic, J. Watson, J. Shao, P. Harrison, Michael J. Manfra, O. Malis Feb 2013

Strong Heavy-To-Light Hole Intersubband Absorption In The Valence Band Of Carbon-Doped Gaas/Alas Superlattices, M. I. Hossain, Z. Ikonic, J. Watson, J. Shao, P. Harrison, Michael J. Manfra, O. Malis

Birck and NCN Publications

We report strong mid-infrared absorption of in-plane polarized light due to heavy-to-light hole intersubband transitions in the valence band of C-doped GaAs quantum wells with AlAs barriers. The transition energies are well reproduced by theoretical calculations including layer inter-diffusion. The inter-diffusion length was estimated to be 8 +/- 2 angstrom, a value that is consistent with electron microscopy measurements. These results highlight the importance of modeling the nanoscale structure of the semiconductors for accurately reproducing intra-band transition energies of heavy carriers such as the holes. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4790305]

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Optical Down-Conversion In Doped Znse:Tb3+ Nanocrystals, Sandip Das, K. C. Mandal Feb 2013

Optical Down-Conversion In Doped Znse:Tb3+ Nanocrystals, Sandip Das, K. C. Mandal

Faculty Publications

No abstract provided.

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Optoelectronic Measurement Of X-Ray Synchrotron Pulses: A Proof Of Concept Demonstration, Stephen M. Durbin, Aamer Mahmood, Marc W. Caffee, Sergei Savikhin, Eric M. Dufresne, Haidan Wen, Yuelin Li Feb 2013

Optoelectronic Measurement Of X-Ray Synchrotron Pulses: A Proof Of Concept Demonstration, Stephen M. Durbin, Aamer Mahmood, Marc W. Caffee, Sergei Savikhin, Eric M. Dufresne, Haidan Wen, Yuelin Li

Birck and NCN Publications

Optoelectronic detection using photoconductive coplanar stripline devices has been applied to measuring the time profile of x-ray synchrotron pulses, a proof of concept demonstration that may lead to improved time-resolved x-ray studies. Laser sampling of current vs time delay between 12 keV x-ray and 800 nm laser pulses reveal the similar to 50 ps x-ray pulse width convoluted with the similar to 200 ps lifetime of the conduction band carriers. For GaAs implanted with 8 MeV protons, a time profile closer to the x-ray pulse width is observed. The protons create defects over the entire depth sampled by the x-rays, …

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A Computational Approach To Optimize Microring Resonators For Biosensing Applications, Justin C. Wirth, B. R. Wenner, M. S. Allen, J. W. Allen, M. Qi Feb 2013

A Computational Approach To Optimize Microring Resonators For Biosensing Applications, Justin C. Wirth, B. R. Wenner, M. S. Allen, J. W. Allen, M. Qi

Birck and NCN Publications

Microcavity structures have recently found utility in chemical/biological sensing applications. The appeal of these structures over other refractive index-based sensing schemes, such as those based on surface plasmon resonance, lies in their potential for producing a highly sensitive response to binding events. High-Q devices, characterized by sharp line widths, are extremely attractive for sensing applications because the bound analyte provides an increased optical pathlength, thus shifting the resonant frequency of the device. In this work, we design and simulate resonant microrings using full-wave finite element models. In addition to structure design, integration of the biological recognition element on the resonator …

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Anti-Bacterial Activity Of Indoor Light Activated Photocatalysts, Suresh Pillai, Michael Seery, Damian Synnott, Stephen Hinder, Georg Michlits Feb 2013

Anti-Bacterial Activity Of Indoor Light Activated Photocatalysts, Suresh Pillai, Michael Seery, Damian Synnott, Stephen Hinder, Georg Michlits

Articles

Nanocrystalline photocatalysts, prepared under ambient conditions using a microwave assisted syn-thesis, show indoor light photocatalytic activity for the degradation of Staphylococcus aureus and Escherichia coli. The zinc sulphide (ZnS) nanomaterials, prepared by a microwave assisted synthesis, are shown to be cubic blende structure with an average crystallite size of 4–6 nm. The anti-bacterial activ-ity of these nanomaterials is investigated under irradiation from a 60 W light bulb and photocatalytic activity is revealed to be due to the defects present in the crystal structure. The ZnS shows anti-bacterial action as both a bacteriostatic and bacteriocidal (88% reduction in the amount of …

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Room-Temperature Organic Ferromagnetism In The Crystalline Poly(3-Hexylthiophene): Phenyl-C61-Butyric Acid Methyl Ester Blend Film, Bin Yang, Zhengguo Xiao, Yongbo Yuan, Tanjore V. Jayaraman, Jeffrey E. Shield, Ralph Skomski, Jinsong Huang Jan 2013

Room-Temperature Organic Ferromagnetism In The Crystalline Poly(3-Hexylthiophene): Phenyl-C61-Butyric Acid Methyl Ester Blend Film, Bin Yang, Zhengguo Xiao, Yongbo Yuan, Tanjore V. Jayaraman, Jeffrey E. Shield, Ralph Skomski, Jinsong Huang

Department of Mechanical and Materials Engineering: Faculty Publications

Pronounced ferromagnetism was observed in a crystalline blend film of conjugated polymer poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) by using magnetic force microscopy measurements. A substantial room-temperature saturation magnetization of about 0.65 emu g−1 was measured by an alternating gradient field magnetometer. Multiple experimental evidences demonstrate the charge transfer from the P3HT to the PCBM and the formation of P3HT crystal domain are expected to be two critical factors for the originals of room-temperature organic ferromagnetism.

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Red-Green-Blue Light Sensitivity Of Oxide Nanowire Transistors For Transparent Display Applications, Sumi Lee, Seongmin Kim, David B. Janes, M. Meyyappan, Sanghyun Ju Jan 2013

Red-Green-Blue Light Sensitivity Of Oxide Nanowire Transistors For Transparent Display Applications, Sumi Lee, Seongmin Kim, David B. Janes, M. Meyyappan, Sanghyun Ju

Birck and NCN Publications

In this study, the sensitivity of oxide nanowire transistors under red (R, 470 nm), green (G, 530 nm), and blue (B, 625 nm) light illumination was investigated. As the wavelength of light illuminating the nanowire channel region became shorter, a negative shift of threshold voltage, degradation of subthreshold slope, and increase of on-current were observed. This phenomenon can be explained in terms of photoinduced holes, creating interfacial traps between the gate dielectric and nanowire channel or reacting with oxygen ions on the surface of the nanowires. Thus, the attempt to minimize characteristic changes due to all RGB light sources was …

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Implementation Of Quantum Logic Gates Using Polar Molecules In Pendular States, Jing Zhu, Sabre Kais, Qi Wei, Dudley Herschbach, Bretislav Friedrich Jan 2013

Implementation Of Quantum Logic Gates Using Polar Molecules In Pendular States, Jing Zhu, Sabre Kais, Qi Wei, Dudley Herschbach, Bretislav Friedrich

Birck and NCN Publications

No abstract provided.

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Quantum Algorithm And Circuit Design Solving The Poisson Equation, Yudong Cao, Anargyros Papageorgiou, Iasonas Petras, Joseph Traub, Sabre Kais Jan 2013

Quantum Algorithm And Circuit Design Solving The Poisson Equation, Yudong Cao, Anargyros Papageorgiou, Iasonas Petras, Joseph Traub, Sabre Kais

Birck and NCN Publications

The Poisson equation occurs in many areas of science and engineering. Here we focus on its numerical solution for an equation in d dimensions. In particular we present a quantum algorithm and a scalable quantum circuit design which approximates the solution of the Poisson equation on a grid with error epsilon. We assume we are given a superposition of function evaluations of the right-hand side of the Poisson equation. The algorithm produces a quantum state encoding the solution. The number of quantum operations and the number of qubits used by the circuit is almost linear in d and polylog in …

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Experimental Study Of Nanofiber Production Through Forcespinning, Simon Padron, Arturo Fuentes, Dumitru Caruntu, Karen Lozano Jan 2013

Experimental Study Of Nanofiber Production Through Forcespinning, Simon Padron, Arturo Fuentes, Dumitru Caruntu, Karen Lozano

Mechanical Engineering Faculty Publications

A newly developed method of producing nanofibers, called forcespinning, has proven to be a viable alternative to mass produce nanofibers. Unlike electrospinning, the most common method currently being employed (which draws fibers through the use of electrostatic force), forcespinning utilizes centrifugal forces which allow for a host of new materials to be processed into nanofibers (given that electric fields are not required) while also providing a significant increase in yield and ease of production. This work presents a detailed explanation of the fiber formation process. The study is conducted using high speed photography to capture the jet initiation process at …

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Co-Electrophoretic Deposition Of Liquid Metal And Silicon For Lithium-Ion Battery Application, Hanfei Zhang Jan 2013

Co-Electrophoretic Deposition Of Liquid Metal And Silicon For Lithium-Ion Battery Application, Hanfei Zhang

Dissertations, Master's Theses and Master's Reports - Open

A low cost electrophoretic deposition (EPD) process was successfully used for liquid metal thin film deposition with a high depositing rate of 0.6 µ/min. Furthermore, silicon nano-powder and liquid metal were then simultaneously deposited as the negative electrode of lithium-ion battery by a technology called co-EPD. The liquid metal was hoping to act as the matrix for silicon particles during lithium ion insertion and distraction. Half-cell testing was performed using as prepared co-EPD sample. An initial discharge capacity of 1500 mAh/g was reported for nano-silicon and galinstan electrode, although the capacity fading issue of these samples was also observed.

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Colloidal Nano-Apatite Particles With Active Luminescent And Magentic Properties For Biotechnology Applications, Rajendra Kasinath, Kumar Ganesan Jan 2013

Colloidal Nano-Apatite Particles With Active Luminescent And Magentic Properties For Biotechnology Applications, Rajendra Kasinath, Kumar Ganesan

Environmental Engineering

Colloidal Nano-apatite Particles with Active Luminescent and Magentic Properties for Biotechnology Applications. The synthesis of functional nano-materials is a burgeoning field that has produced remarkable and consistent breakthroughs over the last two decades. Individual particles have become smaller and shown potential for well defined functionality. However, there are still unresolved problems, a primary one being the loss of functionality and novelty due to uncontrolled aggregation driven by surface energy considerations. As such the first design criteria to harness the true potential of nanoparticles is to prevent unwanted agglomeration by: (1) improving, and, if possible, (2) controlling aggregation behavior. This requires …

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Multiscale Modeling Of Liquid Crystalline/Nanotube Composites, Sharil Patrale Jan 2013

Multiscale Modeling Of Liquid Crystalline/Nanotube Composites, Sharil Patrale

Dissertations, Master's Theses and Master's Reports - Open

The objective of this research is to synthesize structural composites designed with particular areas defined with custom modulus, strength and toughness values in order to improve the overall mechanical behavior of the composite. Such composites are defined and referred to as 3D-designer composites. These composites will be formed from liquid crystalline polymers and carbon nanotubes. The fabrication process is a variation of rapid prototyping process, which is a layered, additive-manufacturing approach. Composites formed using this process can be custom designed by apt modeling methods for superior performance in advanced applications. The focus of this research is on enhancement of Young's …

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