检索结果-南通市图书馆

Stretching the spectra of Kerr frequency combs with self-adaptive boundary silicon waveguides

在线全文

学校读者我要写书评

暂无评论

Advanced Photonics 2020年第4期2卷 29-38页

作者： Jianhao Zhang Vincent Pelgrin carlos alonso-ramos Laurent Vivien Sailing He Eric Cassan UniversitéParis-Saclay CNRSCentre de Nanosciences et de NanotechnologiesPalaiseauFrance Zhejiang University Centre for Optical and Electromagnetic ResearchState Key Laboratory for Modern Optical InstrumentationHangzhouChina

Dispersion engineering of optical waveguides is among the most important steps in enabling the realization of Kerr optical frequency combs.A recurring problem is the limited bandwidth in which the nonlinear phase matching condition is satisfied,due to the dispersion of the *** limitation is particularly stringent in high-index-contrast technologies such as *** propose a general approach to stretch the bandwidth of Kerr frequency combs based on subwavelength engineering of single-mode waveguides with self-adaptive *** wideband flattened dispersion operation comes from the particular property of the waveguide optical mode that automatically self-adapts its spatial profile at different wavelengths to slightly different effective spatial spans determined by its effective index *** flattened dispersion relies on the squeezing of small normal-dispersion regions between two anomalous spectral zones,which enables it to achieve two Cherenkov radiation points and substantially broaden the comb,achieving a bandwidth between 2.2 and 3.4μm *** strategy opens up a design space for trimming the spectra of Kerr frequency combs using high-index-contrast platforms and can provide benefits to various nonlinear applications in which the manipulation of energy spacing and phase matching are pivotal.

关键词： nonlinear optics effective boundary subwavelength grating silicon frequency comb

Supercontinuum generation in silicon photonics platforms

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2022年第3期10卷 I0009-I0022页

作者： Christian Lafforgue Miguel Montesinos-Ballester Thi-Thuy-Duong Dinh Xavier Le Roux Eric Cassan Delphine Marris-Morini carlos alonso-ramos Laurent Vivien Centre de Nanosciences et de Nanotechnologies(C2N) CNRSUniversitéParis-Saclay91120 PalaiseauFrance

Nonlinear optics has not stopped evolving,offering opportunities to develop novel functionalities in *** generation,a nonlinear optical phenomenon responsible for extreme spectral broadening,attracts the interest of researchers due to its high potential in many applications,including sensing,imaging,or optical *** particular,with the emergence of silicon photonics,integrated supercontinuum sources in silicon platforms have seen tremendous progress during the past *** article aims at giving an overview of supercontinuum generation in three main silicon-compatible photonics platforms,namely,silicon,silicon germanium,and silicon nitride,as well as the essential theoretical elements to understand this fascinating phenomenon.

关键词： offering photonics Super

Mode selection and dispersion engineering in Bragg-like slot photonic crystal waveguides for hybrid light-matter interactions

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2018年第1期9卷 54-60页

作者： samuel serna weiwei zhang thi hong cam hoang carlos alonso-ramos delphine marris-morini laurent vivien eric cassan Centre de Nanosciences et de Nanotechnologies UMR 9001 (CNRS/Universite Paris-Sud) Universite Paris-Saclay 91405 Orsay France

We introduce a family of slot photonic crystal waveguides(SPh CWs) for the hybrid integration of low-index active materials in silicon photonics with energy-confinement factors of ~30% in low-index regions. The proposed approach, which is based on a periodic indentation of the etched slot in the middle of the SPh CW, makes it possible to reconcile a simultaneously narrow and wide slot for exploiting the two modes of even symmetry of a SPh CW. The resulting mode-selection mechanism allows a flexible choice of the modes to be used. Furthermore,the proposed structure offers tremendous flexibility for adjusting the dispersive properties of the slot-confined modes, in particular of their slow-light effects. Flat band slow light in a bandwidth of about 60 nm with a group velocity dispersion factor jβ_2 j below 1 ps^2∕mm is numerically demonstrated by this approach, corresponding to a normalized delay bandwidth product of around 0.4. These results, obtained from hollow-core periodic waveguides that are directly designed in view of hybrid integration of active materials in mechanically robust structures(not based on free-standing membranes) could pave the way for the realization of on-chip slow-light bio-sensing,active hybrid-silicon optoelectronic devices, or all-optical hybrid-silicon nonlinear functionalities.

关键词：光子晶体波导通讯技术发展现状

Nonlinear optical properties of integrated GeSbS chalcogenide waveguides

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2018年第5期6卷 I0062-I0067页

作者： SAMUEL SERNA HONGTAO LIN carlos alonso-ramos ANUPAMA YADAV XAVIER LE ROUX KATHLEEN RICHARDSON ERIC CASSAN NICOLAS DUBREUIL JUEJUN HU LAURENT VIVIEN Centre de Nanosciences et de Nanotechnologies (C2N) CNRS Univ.Paris-Sud Université Paris SaclayC2N Orsay Laboratoire Charles Fabry Institut d'Optique Graduate SchoolCNRS Université Paris Saclay Department of Materials Science and Engineering Massachusetts Institute of Technology-MIT College of Optics and Photonics-CREOL University of Central Florida

In this paper, we report the experimental characterization of highly nonlinear Ge Sb S chalcogenide glass *** used a single-beam characterization protocol that accounts for the magnitude and sign of the real and imaginary parts of the third-order nonlinear susceptibility of integrated Ge23 Sb7 S70(GeSbS) chalcogenide glass waveguides in the near-infrared wavelength range at λ =1580 nm. We measured a waveguide nonlinear parameter of 7.0±0.7 W^(-1)· m(-1), which corresponds to a nonlinear refractive index of n_2=0.93±0.08 × 10^(-18) m^2∕W,comparable to that of silicon, but with an 80 times lower two-photon absorption coefficient βTPA=0.010± 0.003 cm∕GW, accompanied with linear propagation losses as low as 0.5 dB/cm. The outstanding linear and nonlinear properties of Ge Sb S, with a measured nonlinear figure of merit FOMTPA=6.0 ±1.4 at λ =1580 nm, ultimately make it one of the most promising integrated platforms for the realization of nonlinear functionalities.

关键词： Sb Nonlinear optical properties of integrated GeSbS chalcogenide waveguides

Silicon photonics phase and intensity modulators for flat frequency comb generation

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2021年第10期9卷 2068-2076页

作者： LUCAS DENIEL ERWAN WECKENMANN DIEGO PÉREZ GALACHO CHRISTIAN LAFFORGUE STÉPHANE MONFRAY carlos alonso-ramos LAURENT BRAMERIE FRÉDÉRIC BOEUF LAURENT VIVEN DELPHINE MARRIS-MORINI Univ.Paris-Saclay CNRSCentre for Nanosciences and Nanotechnologies91120 PalaiseauFrance Univ.Rennes CNRSFOTON-UMR 6082F-22305 LannionFrance ST Microelectronics 850 rue Jean Monnet38920 CrollesFrance Current address:ITEAM Research Institute Universitat Politècnica de ValènciaSpain

Flat electro-optical frequency combs play an important role in a wide range of applications,such as metrology,spectroscopy,or microwave *** a key technology for the integration of optical circuits,silicon photonics could benefit from on-chip,tunable,flat frequency comb *** this article,two different architectures based on silicon modulators are studied for this *** rely on a time to frequency conversion principle to shape the comb *** a numerical model of the silicon traveling-wave phase modulators,their driving schemes are optimized before their performances are simulated and compared.A total of nine lines could be obtained within a 2 dB flatness,with a line-spacing ranging from 0.1 to 7 *** this tunability is a major asset of electro-optical frequency combs,the effect of segmenting the phase modulators is finally investigated,showing that the flat lines spacing could be extended up to 39 GHz by this method.

关键词： phase spacing metrology

Broadband supercontinuum generation in nitrogen-rich silicon nitride waveguides using a 300 mm industrial platform

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2020年第3期8卷 352-358页

作者： CHRISTIAN LAFFORGUE SYLVAIN GUERBER JOAN MANEL RAMIREZ GUILLAUME MARCAUD carlos alonso-ramos XAVIER LE ROUX DELPHINE MARRIS-MORINI ERIC CASSAN CHARLES BAUDOT FRéDéRIC BOEUF SéBASTIEN CREMER STéPHANE MONFRAY LAURENT VIVIEN Centre for Nanoscience and Nanotechnology(C2N) CNRSUniversitéParis-SudUniversitéParis-SaclayUMR 900191405 Orsay CedexFrance Technologie R&D STMicroelectronicsSAS850 rue Jean Monnet38920 CrollesFrance III-V lab a joint venture from Nokia Bell LabsThales and CEA1 Avenue Augustin Fresnel91767 Palaiseau CedexFrance

We report supercontinuum generation in nitrogen-rich(N-rich)silicon nitride waveguides fabricated through back-end complementary-metal-oxide-semiconductor(CMOS)-compatible processes on a 300 mm *** pumping in the anomalous dispersion regime at a wavelength of 1200 nm,two-octave spanning spectra covering the visible and near-infrared ranges,including the O band,were *** calculations showed that the nonlinear index of N-rich silicon nitride is within the same order of magnitude as that of stoichiometric silicon nitride,despite the lower silicon content.N-rich silicon nitride then appears to be a promising candidate for nonlinear devices compatible with back-end CMOS processes.

关键词： waveguides pumping nitride

Third-order nonlinear optical susceptibility of crystalline oxide yttria-stabilized zirconia

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2020年第2期8卷 110-120页

作者： GUILLAUME MARCAUD SAMUEL SERNA KARAMANIS PANAGHIOTIS carlos alonso-ramos XAVIER LE ROUX MATHIAS BERCIANO THOMAS MAROUTIAN GUILLAUME AGNUS PASCAL AUBERT ARNAUD JOLLIVET ALICIA RUIZ-CARIDAD LUDOVIC LARGEAU NATHALIE ISAC ERIC CASSAN SYLVIA MATZEN NICOLAS DUBREUIL MICHEL RERAT PHILIPPE LECOEUR LAURENT VIVIEN Centre de Nanosciences et Nanotechnologies(C2N) Université-Paris-SudCNRS UMR 9001Universite Paris-SaclayOrsay 91405France Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMasschusetts 02139USA Department of Physics Bridgewater State UniversityBridgewaterMassachusetts 02325USA Institut des Sciences Analytiques et de Physico-Chimie pour l’Environnement et les Matériaux CNRSUniversite de Pau et des Pays de l’Adour64053 Pau CedexFrance Laboratoire Charles Fabry Institut d’Optique Graduate SchoolCNRSUniversitéParis-Saclay91127 Palaiseau CedexFrance LP2N Institut d’Optique Graduate SchoolCNRSUniv.Bordeaux33400 TalenceFrance

Nonlinear all-optical technology is an ultimate route for the next-generation ultrafast signal processing of optical communication *** nonlinear functionalities need to be implemented in photonics,and complex oxides are considered as promising candidates due to their wide panel of *** this context,yttria-stabilized zirconia(YSZ)stands out,thanks to its ability to be epitaxially grown on silicon,adapting the lattice for the crystalline oxide family of *** report,for the first time to the best of our knowledge,a detailed theoretical and experimental study about the third-order nonlinear susceptibility in crystalline *** self-phase modulation-induced broadening and considering the in-plane orientation of YSZ,we experimentally obtained an effective Kerr coefficient of n2YSZ=4.0±2×10^-19 m^2·W^-1 in an 8%(mole fraction)YSZ *** agreement with the theoretically predicted n2YSZ=1.3×10^-19 m^2·W^-1,the third-order nonlinear coefficient of YSZ is comparable with the one of silicon nitride,which is already being used in nonlinear *** promising results are a new step toward the implementation of functional oxides for nonlinear optical applications.

关键词： materials. nonlinear crystalline

Unsuccessful tuberculosis treatment outcomes across Brazil's geographical landscape before and during the COVID-19 pandemic:are we truly advancing toward the sustainable development/end TB goal?

在线全文

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2024年第1期13卷 105-106页

作者： Reginaldo Bazon Vaz Tavares Thais Zamboni Berra Yan Mathias Alves Marcela Antunes Paschoal Popolin Antonio carlos Vieira ramos Ariela Fehr Tartaro Clara Ferreira de Souza Ricardo Alexandre Arcencic Department of Maternal-Infant and Public Health Nursing University of São Paulo at Ribeirão Preto College of Nursing (USP/RPCN) Ribeirão Preto São Paulo Brazil Federal University of Tocantins Palmas Campus (FUT) Palmas Brazil State University of Minas Gerais Passos Campus (SUMG) Passos Brazil

Background Tuberculosis is one of the most significant infectious diseases for global public *** reallocation of healthcare resources and the restrictions imposed by the COVID-19 pandemic have hindered access to TB diag-nosis and *** in unfavorable outcomes of the disease have been observed in *** objective of this study was to analyze the spatial distribution of unfavorable TB treatment outcomes in Brazil before and during the *** An ecological study with spatial analysis was conducted with all 5569 municipalities in *** reported cases of tuberculosis between January 2010 and December 2021,as well as reported cases of COVID-19 from Febru-ary 2020 to December 2021,were *** outcomes studied encompass loss to follow-up,drug-resistant tuber-culosis,and *** Getis Ord GI*technique was employed to assess spatial association,and the Kernel density estimator was used to identify areas with concentrated increases or decreases in *** Local Moran's/was used to examine the spatial association between outcomes and cOVID-19 *** study was approved by the Research Ethics Committee of Ribeirao Preto Nursing School,University of Sao *** There were 134,394 cases of loss to follow-up,10,270 cases of drug resistance,and 37,863 *** of high and low values were identified for all three outcomes,indicating significant changes in the spatial distribu-tion *** in concentrations were observed for lost to follow-up cases in the Southeast,while reductions occurred in the Northeast,South,and ***-resistant tuberculosis experienced an increase in the Southern and Southeastern regions and a decrease in the Northeast and ***-related deaths showed notable concentra-tions in the Midwest,Northeast,South,and *** was an increase in high occurrence clusters for deaths after 2020 and 2021 in the *** The pandemic has brought additional chal

关键词： Tuberculosis COVID-19 Spatial analysis Ecological studies

25 Gbps low-voltage hetero-structured silicongermanium waveguide pin photodetectors for monolithic on-chip nanophotonic architectures

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2019年第4期7卷 437-444页

作者： DANIEL BENEDIKOVIC LéOPOLD VIROT GUY AUBIN FARAH AMAR BERTRAND SZELAG BAYRAM KARAKUS JEAN-MICHEL HARTMANN carlos alonso-ramos XAVIER LE ROUX PAUL CROZAT ERIC CASSAN DELPHINE MARRIS-MORINI CHARLES BAUDOT FRéDéRIC BOEUF JEAN-MARC FéDéLI CHRISTOPHE KOPP LAURENT VIVIEN Centre de Nanosciences et de Nanotechnologies CNRS University of Paris-Sud Université Paris-Saclay University Grenoble Alpes and CEA LETI Minatec Campus Technology R&D STMicroelectronics SAS

Near-infrared germanium(Ge) photodetectors monolithically integrated on top of silicon-on-insulator substrates are universally regarded as key enablers towards chip-scale nanophotonics, with applications ranging from sensing and health monitoring to object recognition and optical communications. In this work, we report on the highdata-rate performance pin waveguide photodetectors made of a lateral hetero-structured silicon-Ge-silicon(Si-Ge-Si) junction operating under low reverse bias at 1.55 μm. The pin photodetector integration scheme considerably eases device manufacturing and is fully compatible with complementary metal-oxide-semiconductor technology. In particular, the hetero-structured Si-Ge-Si photodetectors show efficiency-bandwidth products of^9 GHz at-1 V and ~30 GHz at-3 V, with a leakage dark current as low as ~150 nA, allowing superior signal detection of high-speed data traffic. A bit-error rate of 10-9 is achieved for conventional 10 Gbps, 20 Gbps, and25 Gbps data rates, yielding optical power sensitivities of-13.85 dBm,-12.70 dBm, and-11.25 dBm, respectively. This demonstration opens up new horizons towards cost-effective Ge pin waveguide photodetectors that combine fast device operation at low voltages with standard semiconductor fabrication processes, as desired for reliable on-chip architectures in next-generation nanophotonics integrated circuits.

关键词： germanium(Ge) photodetectors chip-scale nanophotonics waveguide photodetectors