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1.
J Nanosci Nanotechnol ; 14(5): 3925-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734665

RESUMO

The energy discontinuity in the valence band (deltaE(v)) of Y2O3-stabilized ZrO2 (YSZ)/InGaZnO4 (IGZO) heterostructures was obtained from X-ray photoelectron spectroscopy (XPS) measurements. The YSZ exhibited a bandgap of 4.4 eV from absorption measurements. A value of deltaE(v) = 0.57 +/- 0.12 eV was obtained by using Ga 2P3/2, Zn 2p3/2 and In 3d5/2 energy levels as references. This implies a conduction band offset (deltaE(c)) of 0.63 eV in YSZ/InGaZnO4 heterostructures and a nested interface band alignment.

2.
Nano Lett ; 12(12): 6152-7, 2012 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-23171302

RESUMO

We demonstrate the formation of a hybridized plasmon-exciton state exhibiting strong exciton-plasmon coupling in ZnO/Zn(0.85)Mg(0.15)O single quantum wells capped with arrays of Al nanodiscs. Tuning the quantum-well width and the diameter and pitch of the Al nanodisc arrays facilitates a transition from the weak-coupling regime into the strong coupling regime. Finite-difference time-domain simulations substantiate the localization of the plasmonic quadrupole moment within the ZnO quantum-well layer, resulting in a hybridized plasmonexciton state demonstrating a Rabi splitting of roughly 15 meV in heterostructures that exhibit a prominent plasmon quadrupole mode. The significant tunability offered by quantum-well heterostructures like those discussed here provides a flexible system for controlling exciton plasmon coupling in a device-compatible thin-film architecture.

3.
J Nanosci Nanotechnol ; 12(4): 3264-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22849102

RESUMO

We investigated the size-dependent electrical conductivities of indium zinc oxide stripes with different widths from 50 nm to 4 microm and with the same thickness of 50 nm deposited by RF magnetron sputtering. The size of the indium zinc oxide stripes was controlled by e-beam lithography. The distance of the two Ti/Au Ohmic electrodes along the indium zinc oxide stripes was kept constant at 25 microm. The electrical conductivity decreased as the size of the indium zinc oxide stripes decreased below a critical width (80 nm). The activation energy, derived from the electric conductivity versus temperature measurement, was dependent on the dimensions of indium zinc oxide stripes. These results can be understood as stemming from surface charge trapping from the absorption of oxygen and/or water vapor, which leads to an increase in the energy difference between the conduction energy band and the Fermi energy.

4.
J Nanosci Nanotechnol ; 12(2): 1415-20, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22629969

RESUMO

ZnO nanowires were grown on indium tin oxide (ITO) coated glass substrates at a low temperature of 90 degrees C using an aqueous solution method. The ZnO seeds were coated on the ITO thin films by using a spin coater. ZnO nanowires were formed in an aqueous solution containing zinc nitrate hexahydrate (Zn(NO3)2 x 6H2O) and hexamethylenetetramine (C6H12N4). The pH value and concentration of the solution play an important role in the growth and morphologies of ZnO nanowires. The size of ZnO naonowires increased as the concentration of the solution increased. It was formed with a top surface of hexagonal and tapered shape at low and high pH values respectively. Additionally, the single crystalline structure and optical property of the ZnO nanowires were investigated using high-resolution transmission electron microscopy and photoluminescence spectroscopy.

5.
J Nanosci Nanotechnol ; 8(1): 99-110, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18468056

RESUMO

A brief review is given of recent developments in wide bandgap semiconductor nanowire synthesis and devices fabricated on these nanostructures. There is strong interest in these devices for applications in UV detection, gas sensors and transparent electronics.

6.
Phys Rev Lett ; 88(9): 097601, 2002 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-11864051

RESUMO

Antiferroelectric behavior is observed in artificially layered KTaO (3)/KNbO (3) perovskite superlattices. While KTaO (3) and KNbO (3) are ferroelectric and paraelectric, respectively, the superlattice appears antiferroelectric based on an increase in the dielectric constant with applied dc bias. This dielectric behavior is inconsistent with the nonlinear response for either paraelectric or ferroelectric materials. However, an increase in the dielectric constant with applied electric field is consistent with antiferroelectric behavior. The antiferroelectric ordering appears to be induced by cation modulation imposed by the superlattice.

7.
Harv Bus Rev ; 78(5): 167-76, 202, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11143152

RESUMO

If you were a military general on the march, you'd want your troops to have plenty of maps--detailed information about the mission they were on, the roads they would travel, the campaigns they would undertake, and the weapons at their disposal. The same holds true in business: a workforce needs clear and detailed information to execute a business strategy successfully. Until now, there haven't been many tools that can communicate both an organization's strategy and the processes and systems needed to implement that strategy. But authors Robert Kaplan and David Norton, cocreators of the balanced scorecard, have adapted that seminal tool to create strategy maps. Strategy maps let an organization describe and illustrate--in clear and general language--its objectives, initiatives, targets markets, performance measures, and the links between all the pieces of its strategy. Employees get a visual representation of how their jobs are tied to the company's overall goals, while managers get a clearer understanding of their strategies and a means to detect and correct any flaws in those plans. Using Mobil North American Marketing and Refining Company as an example, Kaplan and Norton walk through the creation of a strategy map and its four distinct regions--financial, customer, internal process, and learning and growth--which correspond to the four perspectives of the balanced scorecard. The authors show step by step how the Mobil division used the map to transform itself from a centrally controlled manufacturer of commodity products to a decentralized, customer-driven organization.


Assuntos
Comércio/normas , Objetivos Organizacionais , Técnicas de Planejamento , Gestão da Qualidade Total , Eficiência Organizacional , Emprego , Humanos , Cultura Organizacional , Administração de Recursos Humanos , Estados Unidos
8.
Science ; 265(5181): 2074-7, 1994 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-17811410

RESUMO

Pulsed-laser deposition was used to synthesize artificially layered high-temperature superconductors. Thin-film compounds were formed when the constraint of epitaxy was used to stabilize SrCuO(2)-BaCuO(2) superlattices in the infinite layer structure. Using this approach, two new structural families, Ba(2)Srn-1,Cun+1 O2n+2+delta and Ba(4)Srn-1 Cun+3O2n+6+delta have been synthesized; these families superconduct at temperatures as high as 70 kelvin.

9.
Harv Bus Rev ; 70(1): 71-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-10119714

RESUMO

Frustrated by the inadequacies of traditional performance measurement systems, some managers have abandoned financial measures like return on equity and earnings per share. "Make operational improvements and the numbers will follow," the argument goes. But managers do not want to choose between financial and operational measures. Executives want a balanced presentation of measures that allow them to view the company from several perspectives simultaneously. During a year-long research project with 12 companies at the leading edge of performance measurement, the authors developed a "balanced scorecard," a new performance measurement system that gives top managers a fast but comprehensive view of the business. The balanced scorecard includes financial measures that tell the results of actions already taken. And it complements those financial measures with three sets of operational measures having to do with customer satisfaction, internal processes, and the organization's ability to learn and improve--the activities that drive future financial performance. Managers can create a balanced scorecard by translating their company's strategy and mission statements into specific goals and measures. To create the part of the scorecard that focuses on the customer perspective, for example, executives at Electronic Circuits Inc. established general goals for customer performance: get standard products to market sooner, improve customers' time-to-market, become customers' supplier of choice through partnerships, and develop innovative products tailored to customer needs. Managers translated these elements of strategy into four specific goals and identified a measure for each.


Assuntos
Comércio/organização & administração , Auditoria Administrativa/métodos , Sistemas de Informação Administrativa/normas , Comércio/normas , Comportamento do Consumidor/economia , Auditoria Financeira/métodos , Inovação Organizacional , Objetivos Organizacionais , Técnicas de Planejamento , Estados Unidos
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