1,720,969 research outputs found
Photonic Molecules For Optical Signal Processing
No full textWe demonstrate how CMOS compatible photonic molecules (PM) can break the fundamental interdependence among quality factor (Q), channel spacing and size of microring resonators. Different PM architectures are presented for efficient and compact optical signal processing.5455Barea, L.A.M., Vallini, F., De Rezende, G.F.M., Frateschi, N.C., Spectral engineering with cmos compatible soi photonic molecules (2013) IEEE Photonics J., 5 (6), pp. 2202717-2202717Barea, L.A.M., Val Lini, F., Jarschel, P.F., Frateschi, N.C., Silicon technology compatible photonic molecules for compact optical signal processing (2013) Appl. Phys. Lett, 103 (20), p. 201102. , NovSouza, M.C.M.M., Barea, L.A.M., Vallini, F., Rezende, G.F.M., Wiederhecker, G.S., Frateschi, N.C., Embedded coupled microrings with high-finesse and close-spaced resonances for optical signal processing (2014) Opt. Express, 22 (9), pp. 10430-10438. , MayTzuang, L.D., Soltani, M., Lee, Y.H.D., Lipson, M., High rf carrier frequency modulation in silicon resonators by coupling adjacent free-spectral-range modes (2014) Opt. Lett, 39 (7), pp. 1799-1802. , AprXu, Q., Almeida, V.R., Lipson, M., Micrometer-scale all-optical wavelength converter on silicon (2005) Opt. Lett, 30 (20), pp. 2733-2735. , OctLi, Q., Zhang, Z., Liu, F., Qiu, M., Su, Y., Dense wavelength conversion and multicasting in a resonance-split silicon microring (2008) Appl. Phys. Lett, 93 (8), p. 081113. , Au
Ingaasp/inp Qw Microdisk Laser Fabricated By Focused Ion Beam
No full textInGaAsP/InP quantum wells microdisk lasers were fabricated for the evaluation of Ga+ Focused Ion Beam milling of mirrors. Electrical and optical proprieties were investigated and the effects of the milling in the sidewalls were investigated. © 2009 Optical Society of America.Valhala, K.J., Optical Microcavities (2003) Nature, 424, p. 839Mialichi, J.R., Barea, L., von Zuben, A.A., Frateschi, N.C., "Observation of Resonance Modes in InAs/InGaAsP/InP Quantum Dot Microdisk Resonators" (2008), 505. , Electrochemical Society Transactions Microelectronics Technology and Devices. (Pennington NJ USA: Electrochemical Society), v. 14Kim, Y.K., Danner, A.J., Raftery, Jr.J.J., Choquette, K.D., "Focused ion beam nanopatterning for optoelectronic device fabrication," (2005) IEEE J. Sel. Topics Quantum Electron., 11, pp. 1292-1298Schrauwen, J., Van Lysebettens, J., Claes, T., De Vos, K., Bienstman, P., Van Thourhout, D., Baets, R., "Focused-ion-beam fabrication of slots in silicon waveguides and ring resonators" (2008) IEEE Photonics Technol. Lett., 20, pp. 2004-2006Vallini, F., Figueira, D.S.L., Jarschel, P.F., Barea, L.A.M., von Zuben, A.A.G., Filho, A.S., Frateschi, N.C., ".Effects of Ga+ milling on InGaAsP Quantum Well Laser with mirrors etched by Focused Ion Beam" in arXiv:0904.096
Analysis Of Focused Ion Beam Damages In Optoelectronic Devices Fabrication
No full textA study of the damages caused by gallium focused ion beam (FIB) is presented. Potential damages caused by local heating, ion implantation, and selective sputtering are presented. Preliminary analysis shows that local heating is negligible. Gallium implantation is shown to occur over areas tens of nanometers thick. Gallium accumulation as well as selective sputtering during III-V compound milling is expected. Particularly, for GaAs, this effect leads to gallium segregation and the formation of metallic clusters. Microdisks resonators are fabricated using FIB milling of different emission currents. It is shown that for higher emission current, thus higher implantation doses, the cavity quality factor rapidly decreases. © The Electrochemical Society.391299305Electronics and Photonics,IEEE/EDS,ECS,Brazilian Computer Society,Brazilian Microelectronics SocietyVallini, F., Figueira, D.S.L., Jarschel, P.F., Barea, L.A.M., Von Zuben, A.A.G., Filho, A.S., Frateschi, N.C., (2009) J. Vac. Sci. Technol. B, 27, pp. L25Barea, L.A.M., Vallini, F., Vaz, A.R., Mialichi, J.R., Frateschi, N.C., Low-roughness active microdisk resonators fabricated by focused ion beam (2009) J. Vac. Sci. Technol. B, 27, p. 6Chen, H., McKay, H.A., Feenstra, R.M., Aers, G.C., Poole, P.J., Williams, R.L., Charbonneau, S., Mitchell, I.V., (2001) J. Appl. Phys., 89, p. 4815Ziegler, J.F., Biersack, J.P., Littmark, U., (1984) The Stopping and Range of Ions in Solids, 1. , Pergamon Press, New YorkKoren, U., Miller, B.I., Su, Y.K., Koch, T.L., Bowers, J.E., Low-internal-loss separate confinement heterostructure InGaAs/InGaAsP quantum well laser (1987) Appl. Phys. Lett., 51, p. 1744. , TFrateschi, N.C., Levi, A.F.J., The Spectrum of Microdisk Lasers (1996) J. Appl. Phis, 80, p.
Induced Optical Losses In Optoelectronic Devices Due Focused Ion Beam Damages
No full textA study of damages caused by gallium focused ion beam (FIB) into III-V compounds is presented. Potential damages caused by local heating, ion implantation, and selective sputtering are presented. Preliminary analyzes shows that local heating is negligible. Gallium implantation is shown to occur over areas tens of nanometers thick. Gallium accumulation as well as selective sputtering during III-V compounds milling is expected. Particularly, for GaAs, this effect leads to gallium segregation and formation of metallic clusters. Microdisks resonators are fabricated using FIB milling with different emission currents to analyze these effects on a device. It is shown that for higher emission current, thus higher implantation doses, the cavity quality factor rapidly decreases due optical scattering losses induced by implanted gallium atoms.728791Vallini, F., Figueira, D.S.L., Jarschel, P.F., Barea, L.A.M., von Zuben, A.A.G., Filho, A.S., Frateschi, N.C., Effects of Ga + milling on InGaAsP quantum well laser with mirrors milled by focused ion beam (2009) J. Vac. Sci. Technol. B, 27, pp. L25Barea, L.A.M., Vallini, F., Vaz, A.R., Mialichi, J.R., Frateschi, N.C., Low-roughness active microdisk resonators fabricated by focused ion beam (2009) J. Vac. Sci. Technol. B, 27, p. 6Chen, H., McKay, H.A., Feenstra, R.M., Aers, G.C., Poole, P.J., Williams, R.L., Charbonneau, S., Mitchell, I.V., InGaAs/InP quantum well intermixing studied by cross-sectional scanning tunneling microscopy (2001) J. Appl. Phys, 89, p. 4815Ziegler, J.F., Biersack, J.P., Littmark, U., (1984) The Stopping and Range of Ions In Solids, 1. , Pergamon Press, New YorkFrateschi, N.C., Levi, A.F.J., The spectrum of microdisk lasers (1996) J. Appl. Phis, 80, p. 2Koren, U., Miller, B.I., Su, Y.K., Koch, T.L., Bowers, J.E., Low Internal Loss Separate Confinement Heterostructure InGaAs/InGaAsP Quantum Well Laser (1987) Appl. Phys. Lett, 51, p. 1744. , p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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