Rubens' painting as inspiration of a later tapestry: non-invasive analyses provide insight into artworks history.

The 17th century painting Madonna della Cesta by Rubens and its presumed textile reproduction created by Févère for the House of Medici were analysed in comparison. A number of non-invasive optical techniques were applied with the aim to identify similarities and differences between tapestry and painting, in order to shed light on a possible link between their respective authors. The use of a multi-analytical approach proved effective for the acquisition of iconographic, morphological, structural, and compositional information for a comprehensive characterization of the two artworks. While serving as relevant support for documentation and conservation purposes, data so obtained also provide evidence of the uncanny resemblance between the two artworks, and specifically suggest the use by Févère of the same large-scale preparatory drawing (carton) realized by Rubens for his oil painting.Fil: Dal Fovo, Alicia. No especifíca;Fil: Striova, Jana. No especifíca;Fil: Pampaloni, Enrico. No especifíca;Fil: Fedeli, Ana María. Università della Calabria; ItaliaFil: Morita, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Amaya Robayo, Dafne Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Grazzi, Francesco. Centre National de la Recherche Scientifique; FranciaFil: Cimò, Marta. No especifíca;Fil: Cirrincione, Claudia. No especifíca;Fil: Fontana, Raffaella. No especifíca

A CMOS Compatible Silicon-on-Insulator Polarization Rotator Based on Symmetry Breaking of the Waveguide Cross Section

[EN] A polarization rotator in silicon-on-insulator technology based on breaking the symmetry of the waveguide cross section is reported. The 25-mu m-long device is designed to be integrated with standard grating couplers without the need for extra fabrication steps. Hence, fabrication is carried out by a 2-etch-step complementary metal-oxide-semiconductor compatible process using 193-nm deep ultraviolet lithography. A polarization conversion efficiency of more than -0.85 dB with insertion losses ranging from -1 to -2.5 dB over a wavelength range of 30 nm is demonstrated. © 1989-2012 IEEEThis work was supported by the European Commission under Project HELIOS (pHotonics Electronics functional Integration on CMOS), FP7-224312, TEC2008-06333 SINADEC and PROMETEO-2010-087 R&D Excellency Program (NANOMET).Aamer, M.; Gutiérrez Campo, AM.; Brimont, ACJ.; Vermeulen, D.; Roelkens, G.; Fedeli, J.; Håkansson, OA.... (2012). A CMOS Compatible Silicon-on-Insulator Polarization Rotator Based on Symmetry Breaking of the Waveguide Cross Section. IEEE Photonics Technology Letters. 24(22):2031-2034. https://doi.org/10.1109/LPT.2012.2218593S20312034242

10 Gbit/s error-free DPSK modulation using a push-pull dual-drive silicon modulator

[EN] We experimentally demonstrate a high-speed differential phase shift keying (DPSK) modulation using a silicon push-pull operated dual-drive Mach Zehnder modulator (MZM) based on carrier depletion. 5 Gbit/s and 10 Gbit/s error-free modulation is demonstrated by demodulating the generated DPSK modulated signal using a demodulation circuit based on a polarization delay interferometer through the use of a differential group delay (DGD). Furthermore, the potential for higher DPSK modulation speeds up to 20 Gbit/s is also demonstrated. The obtained results validate the potential to achieve higher order modulation formats, such as quadrature phase shift keying (QPSK), by arranging the MZM in a nested configuration. (C) 2013 Elsevier B.V. All rights reserved.Financial supports from HELIOS (Photonics Electronics Functional Integration on CMOS) FP7-224312 and Generalitat Valenciana under PROMETEO-2010-087 R&D Excellency Program (NANOMET) are acknowledged. M. Aamer and P. Sanchis thank Dr. Javier Herrera for his useful help. D.J. Thomson, F.Y. Gardes and G.T. Reed are supported by funding received from the UK EPSRC funding body under the grant “UK Silicon Photonics”.Aamer, M.; Thomson, DJ.; Gutiérrez Campo, AM.; Brimont, ACJ.; Gardes, FY.; Reed, GT.; Fedeli, JM.... (2013). 10 Gbit/s error-free DPSK modulation using a push-pull dual-drive silicon modulator. Optics Communications. 304:107-110. https://doi.org/10.1016/j.optcom.2013.04.051S10711030

Analytical model for calculating the nonlinear distortion in silicon-based electro-optic Mach-Zehnder modulators

[EN] In this study, an analytical model for calculating the nonlinear harmonic/intermodulation distortion for RF signals in silicon-based electro-optic modulators is investigated by considering the nonlinearity on the effective index change curve with the operation point and the device structure simultaneously. Distortion expressions are obtained and theoretical results are presented showing that optimal modulator parameters can be found to linearize it. Moreover, the harmonic distortion of a 1 mm silicon-based asymmetric MZI is RF characterized and used to corroborate the theoretical results. Based on the present model, the nonlinear distortion in terms of bias voltage or operating wavelength is calculated and validated by comparing with the experimental data, showing a good agreement between measurements and theory. Analog photonic link quality parameter like carrier-todistortion is one of the parameters that can be found with that model. Finally, the modulation depth is measured to assure that no over-modulation is produced.This work was supported by the funding from the European Commission under project HELIOS (pHotonics Electronics functional Integration on CMOS), FP7-224312. The work of P. Sanchis and J.-M. Fedeli was supported by the funding funding from TEC2012-38540 LEOMIS, TEC2008-06333 SINADEC, and PROMETEO-2010-087. The work of F. Y. Gardes, D. J. Thomson and G. T. Reed was supported by funding received from the UK EPSRC funding body under the grant "UK Silicon Photonics."Gutiérrez Campo, AM.; Brimont, ACJ.; Herrera Llorente, J.; Aamer, M.; Thomson, DJ.; Gardes, FY.; Reed, GT.... (2013). Analytical model for calculating the nonlinear distortion in silicon-based electro-optic Mach-Zehnder modulators. Journal of Lightwave Technology. 31(23):3603-3612. https://doi.org/10.1109/JLT.2013.2286838S36033612312

Ring-assisted Mach-Zehnder interferometer silicon modulator for enhanced performance

[EN] A high-speed ring-assisted Mach-Zehnder interferometer (RAMZI) silicon modulator is reported and experimentally demonstrated. The RAMZI optical structure relaxes the optimum coupling condition of the ring without degrading the modulator performance, which therefore improves the modulator robustness against fabrication deviations and could eventually lead to an enhanced modulation bandwidth. Hence, our RAMZI silicon modulator, based on carrier depletion in a pipin active structure, exhibits a 3 dB electro-optical bandwidth of 19 GHz, enabling up to 20 Gbit/s data transmission over a RF/optical interaction length of only similar to 200 mu m.This work was supported in part by the European Commission under project HELIOS (pHotonics Electronics functional Integration on CMOS), FP7-224312. The work of P. Sanchis and J. Marti was supported in part by the R&D Excellency Program (NANOMET) under Grant TEC2008-06360 DEMOTEC, Grant TEC2008-06333 SINADEC, and Grant PROMETEO-2010-087. The work of D. Marris-Morini and L. Vivien was supported in part by the French ANR under project SILVER.Brimont, ACJ.; Gutiérrez Campo, AM.; Rasigade, G.; Ziebell, M.; Marris-Morini, D.; Fedeli, JM.; Vivien, L.... (2012). Ring-assisted Mach-Zehnder interferometer silicon modulator for enhanced performance. Journal of Lightwave Technology. 30(1):9-14. https://doi.org/10.1109/JLT.2011.2176314S91430