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Produção e caracterização de guias de onda de telureto e germanato para aplicações em optoeletrônica.; Fabrication and characterization of tellurite and germanate waveguides for optoelectronics applications.

Del Cacho, Vanessa Duarte
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 29/03/2010 PT
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Este trabalho tem como objetivo a confecção e caracterização de guias de onda de GeO2-PbO e TeO2-ZnO. Os guias de onda foram produzidos a partir de filmes finos e vidros usando diferentes procedimentos. Os filmes foram produzidos usando a técnica de RF "magnetron sputtering" e foram caracterizados por meio de várias análises. Em especial, a microscopia eletrônica de varredura foi indispensável para definição dos melhores processos para a construção dos guias de onda, o maior desafio do trabalho, pois não havia na literatura trabalhos desta natureza com os materiais em questão. Os guias nos filmes foram construídos sobre substratos de silício, utilizando-se os processos convencionais de microeletrônica: limpeza química, oxidação térmica, deposição por "sputtering", litografia óptica e corrosões úmidas e por plasma. Os diversos testes realizados com estes processos permitiram encontrar as melhores condições (corrosão por plasma de SF6, resiste AZ-5214 e remoção com microstripper 2001) para a implementação de guias de onda "rib" com largura de 1 à 10 m usando profundidades de 70 nm para o guia de GeO2-PbO e de 90 nm para o guia de TeO2-ZnO. Os guias de ondas rib de PbO-GeO2 e TeO2-ZnO foram analisados opticamente quanto às perdas por propagação. Ambos apresentaram guiamento multimodo (TE) e os valores de atenuação experimentais obtidos foram de 2...

Injectable, Cellular-Scale Optoelectronics with Applications for Wireless Optogenetics

Kim, Tae-il; McCall, Jordan G.; Jung, Yei Hwan; Huang, Xian; Siuda, Edward R.; Li, Yuhang; Song, Jizhou; Song, Young Min; Pao, Hsuan An; Kim, Rak-Hwan; Lu, Chaofeng; Lee, Sung Dan; Song, Il-Sun; Shin, Gun Chul; Al-Hasani, Ream; Kim, Stanley; Tan, Meng Peu
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 12/04/2013 EN
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Successful integration of advanced semiconductor devices with biological systems will accelerate basic scientific discoveries and their translation into clinical technologies. In neuroscience generally, and in optogenetics in particular, an ability to insert light sources, detectors, sensors and other components into precise locations of the deep brain could yield versatile and important capabilities. Here, we introduce an injectable class of cellular-scale optoelectronics that offers such features, with examples of unmatched operational modes in optogenetics, including completely wireless and programmed complex behavioral control over freely moving animals. The ability of these ultrathin, mechanically compliant, biocompatible devices to afford minimally invasive operation in the soft tissues of the mammalian brain foreshadow applications in other organ systems, with potential for broad utility in biomedical science and engineering.

Ordered organic solids via liquid crystalline mesomorphism for optoelectronics

Wei, Simon Ku-Hsien (1980 - ); Chen, Shaw H.
Fonte: University of Rochester Publicador: University of Rochester
Tipo: Tese de Doutorado Formato: Number of Pages:xix, 113 leaves; Illustrations:ill. (some col.)
ENG
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Thesis (Ph. D.)--University of Rochester. Dept. of Chemical Engineering, 2011.; Orientation of [pi]-conjugated molecules across a large area without defects is potentially useful to a host of optoelectronic devices. Solution cast films of active materials have been processed into uniaxially oriented and helically stacked conjugated molecules mediated by nematic and cholesteric liquid crystalline mesomorphism, respectively. In this thesis, both glassy-nematic and glassy-cholesteric films were prepared via thermal annealing of thermotropic liquid crystals at an elevated temperature and solvent-vapor annealing of lyotropic liquid crystals at room temperature on both rubbed polyimide alignment and noncontact photoalignment layers followed by cooling through glass transition temperature and thorough drying in vacuo, respectively. Major accomplishments are recapitulated as follows. Mixtures of pentafluorenes doped with a red-emitting oligofluorene were prepared between rubbed polyimide alignment layers into constant-pitch glassy-cholesteric liquid crystal films, yielding lasing thresholds and efficiencies comparable to widely reported fluid cholesteric liquid crystal lasers. Robust glassy-cholesteric liquid crystal films, however, produced temporally stable lasing output...

Zn3As2 Nanowires and nanoplatelets: highly efficient infrared emission and photodetection by an earth abundant material

Burgess, Tim; Caroff, Philippe; Wang, Yuda; Badada, Bekele H.; Jackson, Howard E.; Smith, Leigh M.; Guo, Yanan; Tan, Hark Hoe; Jagadish, Chennupati
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artigo de Revista Científica Formato: 8 pages
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The development of earth abundant materials for optoelectronics and photovoltaics promises improvements in sustainability and scalability. Recent studies have further demonstrated enhanced material efficiency through the superior light management of novel nanoscale geometries such as the nanowire. Here we show that an industry standard epitaxy technique can be used to fabricate high quality II-V nanowires (1D) and nanoplatelets (2D) of the earth abundant semiconductor Zn3As2. We go on to establish the optoelectronic potential of this material by demonstrating efficient photoemission and detection at 1.0 eV, an energy which is significant to the fields of both photovoltaics and optical telecommunications. Through dynamical spectroscopy this superior performance is found to arise from a low rate of surface recombination combined with a high rate of radiative recombination. These results introduce nanostructured Zn3As2 as a high quality optoelectronic material ready for device exploration.; T.B., P.C., Y.G., H.H.T., and C.J. acknowledge the Australian Research Council. T.B., P.C., Y.G., H.H.T., and C.J. thank the Australian National Fabrication Facility for access to the growth and microscopy facilities and Centre for Advanced Microscopy and Australian Microscopy and Microanalysis Research Facility for access to microscopy facilities used in this work. Y.W....

Single nanowire photoconductive terahertz detectors

Peng, Kun; Parkinson, Patrick; Fu, Lan; Gao, Qiang; Jiang, Nian; Guo, Ya-Nan; Wang, Fan; Joyce, Hannah J.; Boland, Jessica L.; Tan, Hark Hoe; Jagadish, Chennupati; Johnston, Michael B.
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artigo de Revista Científica Formato: 5 pages
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Spectroscopy and imaging in the terahertz (THz) region of the electromagnetic spectrum has proven to provide important insights in fields as diverse as chemical analysis, materials characterization, security screening, and nondestructive testing. However, compact optoelectronics suited to the most powerful terahertz technique, time-domain spectroscopy, are lacking. Here, we implement single GaAs nanowires as microscopic coherent THz sensors and for the first time incorporated them into the pulsed time-domain technique. We also demonstrate the functionality of the single nanowire THz detector as a spectrometer by using it to measure the transmission spectrum of a 290 GHz low pass filter. Thus, nanowires are shown to be well suited for THz device applications and hold particular promise as near-field THz sensors.; We acknowledge the Australian National Fabrication Facility (ANFF) ACT node for access to the fabrication facilities used in this work and the Engineering and Physical Sciences Research Council (EPSRC) for financial support.

Nanocrystal-based optoelectronic devices in plamonic nanojunctions

Evans, Kenneth
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
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Optical trapping is an important tool for studying and manipulating nanoscale objects. Recent experiments have shown that subwavelength control of nanoparticles is possible by using patterned plasmonic nanostructures, rather than using a laser directly, to generate the electric fields necessary for particle trapping. In this thesis we present a theoretical model and experimental evidence for plasmonic optical trapping in nanoscale metal junctions. Further, we examine the use of the resultant devices as ultrasmall photodectors. Electromigrated nanojunctions, or “nanogaps”, have a well-established plasmon resonance in the near-IR, leading to electric field enhancements large enough for single-molecule sensitivity in Surface-Enhance Raman (SERS) measurements. While molecule-based devices have been carefully studied, optically and electrically probing individual quantum dots in nanoscale metal junctions remains relatively unexplored. Plasmon-based optical trapping of quantum dots into prefabricated structures could allow for inexpensive, scalable luminescent devices which are fully integrable into established silicon-based fabrication techniques. Additionally, these metal-nanocrystal-metal structures are ideal candidates to study optoelectronics in ultrasmall nanocrystals-based structures...

The impact of manufacturing offshore on technology development paths in the automotive and optoelectronics industries

Fuchs, Erica R. H. (Erica Renee H.), 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 209 p.
ENG
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This dissertation presents a two-case study of the impact of manufacturing offshore on the technology trajectory of the firm and the industry. It looks in particular at the automotive and optoelectronics industries. The dissertation uses an innovative combination of engineering modeling and qualitative research methods to provide insights into this question. The results suggest an important difference between the two cases. In the automotive case, the results do not show that manufacturing offshore changes the path of technology development. In the optoelectronics case, the results do suggest that manufacturing offshore may be changing the path of technology development. The cross-case analysis reveals several important similarities between the two cases: (1) the relative economic positions of the emerging technology and the prevailing design shift when production is transferred to developing East Asia; (2) while the emerging design is more cost-competitive in the U.S. production structure, the prevailing design is more cost-competitive in the developing East Asia production structure; (3) firms initially do not understand the implications of moving offshore for the competitiveness of their designs; (4) firms choose to produce the prevailing design offshore; and (5) although the firms' decisions to produce the prevailing design offshore are rational in a static model...

Terahertz Optoelectronics with Surface Plasmon Polariton Diode

Vinnakota, Raj K.; Genov, Dentcho A.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 09/05/2014 EN
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The field of plasmonics has experience a renaissance in recent years by providing a large variety of new physical effects and applications. Surface plasmon polaritons, i.e. the collective electron oscillations at the interface of a metal/semiconductor and a dielectric, may bridge the gap between electronic and photonic devices, provided a fast switching mechanism is identified. Here, we demonstrate a surface plasmon-polariton diode (SPPD) an optoelectronic switch that can operate at exceedingly large signal modulation rates. The SPPD uses heavily doped p-n junction where surface plasmon polaritons propagate at the interface between n and p-type GaAs and can be switched by an external voltage. The devices can operate at transmission modulation higher than 98% and depending on the doping and applied voltage can achieve switching rates of up to 1 THz. The proposed switch is compatible with the current semiconductor fabrication techniques and could lead to nanoscale semiconductor-based optoelectronics.

Regenerative oscillation and four-wave mixing in graphene optoelectronics

Gu, Tingyi; Petrone, Nick; McMillian, James F.; van der Zande, Arend; Yu, Mingbin; Lo, Guo-Qiang; Kwong, Dim-Lee; Hone, James; Wong, Chee-Wei
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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The unique linear and massless band structure of graphene, in a purely two-dimensional Dirac fermionic structure, have led to intense research spanning from condensed matter physics to nanoscale device applications covering the electrical, thermal, mechanical and optical domains. Here we report three consecutive first-observations in graphene-silicon hybrid optoelectronic devices: (1) ultralow power resonant optical bistability; (2) self-induced regenerative oscillations; and (3) coherent four-wave mixing, all at a few femtojoule cavity recirculating energies. These observations, in comparison with control measurements with solely monolithic silicon cavities, are enabled only by the dramatically-large and chi(3) nonlinearities in graphene and the large Q/V ratios in wavelength-localized photonic crystal cavities. These results demonstrate the feasibility and versatility of hybrid two-dimensional graphene-silicon nanophotonic devices for next-generation chip-scale ultrafast optical communications, radio-frequency optoelectronics, and all-optical signal processing.; Comment: Accepted at Nature Photonics, July (2012)

Optoelectronics with electrically tunable PN diodes in a monolayer dichalcogenide

Baugher, Britton W. H.; Churchill, Hugh O. H.; Yang, Yafang; Jarillo-Herrero, Pablo
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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One of the most fundamental devices for electronics and optoelectronics is the PN junction, which provides the functional element of diodes, bipolar transistors, photodetectors, LEDs, and solar cells, among many other devices. In conventional PN junctions, the adjacent p- and n-type regions of a semiconductor are formed by chemical doping. Materials with ambipolar conductance, however, allow for PN junctions to be configured and modified by electrostatic gating. This electrical control enables a single device to have multiple functionalities. Here we report ambipolar monolayer WSe2 devices in which two local gates are used to define a PN junction exclusively within the sheet of WSe2. With these electrically tunable PN junctions, we demonstrate both PN and NP diodes with ideality factors better than 2. Under excitation with light, the diodes show photodetection responsivity of 210 mA/W and photovoltaic power generation with a peak external quantum efficiency of 0.2%, promising numbers for a nearly transparent monolayer sheet in a lateral device geometry. Finally, we demonstrate a light-emitting diode based on monolayer WSe2. These devices provide a fundamental building block for ubiquitous, ultra-thin, flexible, and nearly transparent optoelectronic and electronic applications based on ambipolar dichalcogenide materials.; Comment: 14 pages...

Wafer-scale growth of large arrays of perovskite microplate crystals for functional electronics and optoelectronics

Wang, Gongming; Li, Dehui; Cheng, Hung-Chieh; Li, Yongjia; Chen, Chih-Yen; Yin, Anxiang; Zhao, Zipeng; Lin, Zhaoyang; Wu, Hao; He, Qiyuan; Ding, Mengning; Liu, Yuan; Huang, Yu; Duan, Xiangfeng
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/10/2015
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Methylammonium lead iodide perovskite has attracted intensive interest for its diverse optoelectronic applications. However, most studies to date have been limited to bulk thin films that are difficult to implement for integrated device arrays because of their incompatibility with typical lithography processes. We report the first patterned growth of regular arrays of perovskite microplate crystals for functional electronics and optoelectronics. We show that large arrays of lead iodide microplates can be grown from an aqueous solution through a seeded growth process and can be further intercalated with methylammonium iodide to produce perovskite crystals. Structural and optical characterizations demonstrate that the resulting materials display excellent crystalline quality and optical properties. We further show that perovskite crystals can be selectively grown on prepatterned electrode arrays to create independently addressable photodetector arrays and functional field effect transistors. The ability to grow perovskite microplates and to precisely place them at specific locations offers a new material platform for the fundamental investigation of the electronic and optical properties of perovskite materials and opens a pathway for integrated electronic and optoelectronic systems.; Comment: 8 pages...

Rediscovering Black Phosphorus: A Unique Anisotropic 2D Material for Optoelectronics and Electronics

Xia, Fengnian; Wang, Han; Jia, Yichen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Anisotropy refers to the property of a material exhibiting directionally dependent features. In this paper, we introduce black phosphorous (BP), the most stable allotrope of phosphorus in layered orthorhombic structure with a bandgap of 0.3 eV in bulk, as a unique 2D material in which electrons, phonons and their interactions with photons behave in a highly anisotropic manner within the plane of the layers. The unique anisotropic nature of BP thin films is revealed using angle-resolved Raman and infrared spectroscopies, together with angle-resolved transport study. For 15 nm thick BP, we measure Hall mobility of 1000 and 600 cm^2/Vs for holes along the light (x) and heavy (y) effective mass directions, respectively, at 120 K. These BP thin films also exhibit large and anisotropic in-plane optical conductivity from 2 to 5 micrometer wavelength. Field effect transistors using 4 to 30 layers of BP (2 to 15 nm) as channel material exhibit an on-off current ratio exceeding 10^5, a field-effect mobility of 205 cm^2/Vs, and good saturation properties all at room temperature, suggesting its promising future in high performance thin film electronics. By introducing narrow bandgap BP into the 2D material family, we fill the space between semi-metallic graphene and large bandgap TMDCs...

Graphene Photonics and Optoelectronics

Bonaccorso, F.; Sun, Z.; Hasan, T.; Ferrari, A. C.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/06/2010
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The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential to be in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultra-wide-band tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light emitting devices, to touch screens, photodetectors and ultrafast lasers. Here we review the state of the art in this emerging field.; Comment: Review Nature Photonics, in press

Valley Dependent Optoelectronics from Inversion Symmetry Breaking

Yao, Wang; Xiao, Di; Niu, Qian
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Inversion symmetry breaking allows contrasted circular dichroism in different k-space regions, which takes the extreme form of optical selection rules for interband transitions at high symmetry points. In materials where band-edges occur at noncentral valleys, this enables valley dependent interplay of electrons with light of different circular polarizations, in analogy to spin dependent optical activities in semiconductors. This discovery is in perfect harmony with the previous finding of valley contrasted Bloch band features of orbital magnetic moment and Berry curvatures from inversion symmetry breaking [Phys. Rev. Lett. 99, 236809 (2007)]. A universal connection is revealed between the k-resolved optical oscillator strength of interband transitions, the orbital magnetic moment and the Berry curvatures, which also provides a principle for optical measurement of orbital magnetization and intrinsic anomalous Hall conductivity in ferromagnetic systems. The general physics is demonstrated in graphene where inversion symmetry breaking leads to valley contrasted optical selection rule for interband transitions. We discuss graphene based valley optoelectronics applications where light polarization information can be interconverted with electronic information.; Comment: Expanded version...

Tensile-Strained Germanium-on-Insulator Substrate Fabrication for Silicon-Compatible Optoelectronics

Jain, J. Raja; Ly-Gagnon, Dany-Sebastien; Balram, Krishna C.; White, Justin S.; Brongersma, Mark L.; Miller, David A. B.; Howe, Roger T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We present a method to fabricate tensile-strained germanium-on-insulator (GOI) substrates using heteroepitaxy and layer transfer techniques. The motivation is to obtain a high-quality wafer-scale GOI platform suitable for silicon-compatible optoelectronic device fabrication. Crystal quality is assessed using X-Ray Diffraction (XRD) and Transmission Electron Microscopy. A biaxial tensile film strain of 0.16% is verified by XRD. Suitability for device manufacturing is demonstrated through fabrication and characterization of metal-semiconductor-metal photodetectors that exhibit photoresponse beyond 1.55 {\mu}m. The substrate fabrication process is compatible with complementary metal-oxide-semiconductor manufacturing and represents a potential route to wafer-scale integration of silicon-compatible optoelectronics.

Interfacial structure in organic optoelectronics

Turak, Ayse; Grozea, Dan; Huang, Chanjun; Lu, Zheng-Hong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/08/2012
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The interfacial structure plays a critical role in modern optoelectronics. Currently multilayer electrodes are used to optimize the injection and lifetime properties. The choice of interlayer is not universal, with different effects for the same material with different capping metals. Using a novel in-situ characterization method with X-ray photoelectron spectroscopy, the organic/inorganic interface in OLEDs was examined for two common cathode metals with a LiF interlayer. The impact of the interfacial layer on the performance of devices can be attributed to the bulk lattice matching of the interfacial layer and of the by-products of interfacial oxidation, and the metallic cathode.; Comment: 2 pages, proceedings of the 4th UT2 Graduate Student Workshop (University of Tokyo - University of Toronto), 2005

The optical links of the ATLAS SemiConductor tracker

Bernabeu Verdú, José; Fuster, Juan; García García, Carmen; Lozano Fantoba, Manuel; Ullán Comes, Miguel; Escobar, Carlos
Fonte: Institute of Physics Publishing Publicador: Institute of Physics Publishing
Tipo: Artículo Formato: 2373 bytes; text/plain
ENG
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28 pages, 17 figures.-- PACS nrs.: 42.88.+h, 04.40.Nr, 85.40, 85.60.-- ISI Article Identifier: 000253652000008.-- et al.; Optical links are used for the readout of the 4088 silicon microstrip modules that make up the SemiConductor Tracker of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The optical link requirements are reviewed, with particular emphasis on the very demanding environment at the LHC. The on-detector components have to operate in high radiation levels for 10 years, with no maintenance, and there are very strict requirements on power consumption, material and space. A novel concept for the packaging of the on-detector optoelectronics has been developed to meet these requirements. The system architecture, including its redundancy features, is explained and the critical on-detector components are described. The results of the extensive Quality Assurance performed during all steps of the assembly are discussed.; We acknowledge the support of the funding authorities of the collaborating institutes including the Ministry of Education, Culture, Sports, Science and Technology, Japan, The Japan Society for the Promotion of Science, The Netherlands Institute for Fundamental Matter Research (FOM), The Netherlands Organisation for Scientific Research (NWO)...

Matrix-Assisted Pulsed Laser Evaporation of Conjugated Polymer and Hybrid Nanocomposite Thin Films: A Novel Deposition Technique for Organic Optoelectronic Devices

Pate, Ryan Jared
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2011
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This dissertation develops a novel application of the resonant-infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) technique toward the end goal of conjugated-polymer-based optoelectronic device fabrication. Conjugated polymers are attractive materials that are being investigated in the development of efficient optoelectronic devices due to their inexpensive material costs. Moreover, they can easily be combined with inorganic nanomaterials, such as colloidal quantum dots (CQDs), so as to realize hybrid nanocomposite-based optoelectronic devices with tunable optoelectronic characteristics and enhanced desirable features. One of the most significant challenges to the realization of optimal conjugated polymer-CQD hybrid nanocomposite-based optoelectronics has been the processes by which these materials are deposited as thin films, that is, conjugated polymer thin film processing techniques lack sufficient control so as to maintain preferred optoelectronic device behavior. More specifically, conjugated-polymer-based optoelectronics device operation and efficiency are a function of several attributes, including surface film morphology, internal polymer chain morphology, and the distribution and type of nanomaterials in the film bulk. Typical conjugated-polymer thin-film fabrication methodologies involve solution-based deposition...

Competition, knowledge spillover, and innovation: technological development of semiconductor lasers, 1960- 1990

Shimizu, Hiroshi
Fonte: London School of Economics and Political Science Thesis Publicador: London School of Economics and Political Science Thesis
Tipo: Thesis; NonPeerReviewed Formato: application/pdf
Publicado em //2007 EN
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Knowledge plays an important role in economic growth. The role of technological knowledge significantly increased after the Industrial Revolution. Firms internalised technological knowledge in their R&D laboratories and placed knowledge creation in a central position in their business strategies. Both the stock and flow of technological knowledge and the tight interaction among science and engineering became indispensable to the competitive advantage of industry, as well as modern economic growth. Directing its attention to knowledge creation and spillover, this thesis scrutinises the development of semiconductor lasers from 1960 to 1990. The semiconductor laser became one of the most important developments in the optoelectronics industry underlying the drastic changes that took place during the last half of the twentieth century in information technology, and it has become the most widely used laser since the 1980s. Reviewing the optoelectronics industry in the U.S. and Japan, the Japan Technology Evaluation Center (JTEC) found that “Japan clearly led in consumer optoelectronics, that both countries were competitive in communications and networks, and that the United States held a clear lead in custom optoelectronics.” “Japan’s lead in high-volume consumer optoelectronics and related technologies gave it a dominant share of the overall global optoelectronics market.” This thesis explores how the patterns of comparative advantages emerged...

Implementation of a 10.24 GS/s 12-bit Optoelectronics Analog-to-Digital Converter Based on a Polyphase Demultiplexing Architecture

Villa-Angulo,C.; Hernandez-Fuentes,I. O.; Villa-Angulo,R.; Ahumada-Valdez,S. E.; Ramos-Irigoyen,R. A.; Donkor,E.
Fonte: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico Publicador: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2013 EN
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In this paper we present the practical implementation of a high-speed polyphase sampling and demultiplexing architecture for optoelectronics analog-to-digital converters (OADCs). The architecture consists of a one-stage divideby-eight decimator circuit where optically-triggered samplers are cascaded to sample an analog input signal, and demultiplex different phases of the sampled signal to yield low data rate for electronic quantization. Electrical-in to electrical-out data format is maintained through the sampling, demultiplexing and quantization processes of the architecture thereby avoiding the need for electrical-to-optical and optical-to-electrical signal conversions. We experimentally demonstrate a 10.24 giga samples per second (GS/s), 12-bit resolution OADC system comprising the optically-triggered sampling circuits integrated with commercial electronic quantizers. Measurements performed on the OADC yielded an effective bit resolution (ENOB) of 10.3 bits, spurious free dynamic range (SFDR) of -32 dB and signal-to-noise and distortion ratio (SNDR) of 63.7 dB.