Suchergebnisse

709 786 12 3 ; S ; [EN] Programmable integrated photonics is an emerging new paradigm that aims at designing common integrated optical hardware resource configurations, capable of implementing an unconstrained variety of functionalities by suitable programming, following a parallel but not identical path to that of integrated electronics in the past two decades of the last century. Programmable integrated photonics is raising considerable interest, as it is driven by the surge of a considerable number of new applications in the fields of telecommunications, quantum information processing, sensing, and neurophotonics, calling for flexible, reconfigurable, low-cost, compact, and low-power-consuming devices that can cooperate with integrated electronic devices to overcome the limitation expected by the demise of Moore¿s Law. Integrated photonic devices exploiting full programmability are expected to scale from application-specific photonic chips (featuring a relatively low number of functionalities) up to very complex application-agnostic complex subsystems much in the same way as field programmable gate arrays and microprocessors operate in electronics. Two main differences need to be considered. First, as opposed to integrated electronics, programmable integrated photonics will carry analog operations over the signals to be processed. Second, the scale of integration density will be several orders of magnitude smaller due to the physical limitations imposed by the wavelength ratio of electrons and light wave photons. The success of programmable integrated photonics will depend on leveraging the properties of integrated photonic devices and, in particular, on research into suitable interconnection hardware architectures that can offer a very high spatial regularity as well as the possibility of independently setting (with a very low power consumption) the interconnection state of each connecting element. Integrated multiport interferometers and waveguide meshes provide regular and periodic geometries, formed by ...

Machine learning in photonics has potential in many industries. However, research on patent portfolios is still lacking. The purpose of this study was to assess the status of machine learning in photonics technology and patent portfolios and investigate major assignees to generate a better understanding of the developmental trends of machine learning in photonics. This can provide governments and industry with a resource for planning strategic development. I used data-mining methods (correspondence analysis and K-means clustering) to explore competing technological and strategic-group relationships within the field of machine learning in photonics. The data were granted patents in the USPTO database from 2019 to 2020. The results reveal that patents were primarily in image data processing, electronic digital data processing, wireless communication networks, and healthcare informatics and diagnosis. I assessed the relative technological advantages of various assignees and propose policy recommendations for technology development.

"© © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works." ; A system to interrogate photonic sensors based on long weak fiber Bragg gratings (FBGs) is illustrated and experimentally demonstrated. The FBG sensor is able to detect and measure the precise location of several spot events. The principle of operation is based on a technique used to analyze microwave photonics filters. The long weak FBGs are used as quasi-distributed sensors. Several events can be detected along the FBG device with a spatial accuracy of 1 mm using a modulator and a photodetector with a modest bandwidth of 500 MHz. The simple proposed scheme is intrinsically robust against environmental changes and easy to reconfigure. ; This work was supported in part by the COST Action under Grant TD1001 through the OFSeSa Project, in part by the Infraestructura through the Federacion Espanola de Enfermedades Raras Project under Grant UPVOV08-3E-008 and Grant UPVOV10-3E-492, in part by the Spanish Ministerio de Ciencia e Innovacion under Project TEC2011-29120-C05-05, in part by the Valencia Government through the Ayuda Complementaria Project under Grant ACOMP/2013/146, in part by the Research Excellency Award Program GVA PROMETEO under Grant 2013/012, and in part by the Swiss Commission for Technology and Innovation under Project 13122.1. ; Lavinia Ricchiuti, A.; Barrera Vilar, D.; Sales Maicas, S.; Thevenaz, L.; Capmany Francoy, J. (2014). Long Weak FBG Sensor Interrogation Using Microwave Photonics Filtering Technique. IEEE Photonics Technology Letters. 26(20):2039-2042. https://doi.org/10.1109/LPT.2014.2345611 ; S ; 2039 ; 2042 ; 26 ; 20

2039 2042 26 20 ; S ; "© © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works." A system to interrogate photonic sensors based on long weak fiber Bragg gratings (FBGs) is illustrated and experimentally demonstrated. The FBG sensor is able to detect and measure the precise location of several spot events. The principle of operation is based on a technique used to analyze microwave photonics filters. The long weak FBGs are used as quasi-distributed sensors. Several events can be detected along the FBG device with a spatial accuracy of <1 mm using a modulator and a photodetector with a modest bandwidth of <500 MHz. The simple proposed scheme is intrinsically robust against environmental changes and easy to reconfigure. This work was supported in part by the COST Action under Grant TD1001 through the OFSeSa Project, in part by the Infraestructura through the Federacion Espanola de Enfermedades Raras Project under Grant UPVOV08-3E-008 and Grant UPVOV10-3E-492, in part by the Spanish Ministerio de Ciencia e Innovacion under Project TEC2011-29120-C05-05, in part by the Valencia Government through the Ayuda Complementaria Project under Grant ACOMP/2013/146, in part by the Research Excellency Award Program GVA PROMETEO under Grant 2013/012, and in part by the Swiss Commission for Technology and Innovation under Project 13122.1. Lavinia Ricchiuti, A.; Barrera Vilar, D.; Sales Maicas, S.; Thevenaz, L.; Capmany Francoy, J. (2014). Long Weak FBG Sensor Interrogation Using Microwave Photonics Filtering Technique. IEEE Photonics Technology Letters. 26(20):2039-2042. doi:10.1109/LPT.2014.2345611

Nonlinear optics is an increasingly important field for scientific and technological applications, owing to its relevance and potential for optical and optoelectronic technologies. Currently, there is an active search for suitable nonlinear material systems with efficient conversion and a small material footprint. Ideally, the material system should allow for chip integration and room-temperature operation. Two-dimensional materials are highly interesting in this regard. Particularly promising is graphene, which has demonstrated an exceptionally large nonlinearity in the terahertz regime. Yet, the light–matter interaction length in two-dimensional materials is inherently minimal, thus limiting the overall nonlinear optical conversion efficiency. Here, we overcome this challenge using a metamaterial platform that combines graphene with a photonic grating structure providing field enhancement. We measure terahertz third-harmonic generation in this metamaterial and obtain an effective third-order nonlinear susceptibility with a magnitude as large as 3 × 10–8 m2/V2, or 21 esu, for a fundamental frequency of 0.7 THz. This nonlinearity is 50 times larger than what we obtain for graphene without grating. Such an enhancement corresponds to a third-harmonic signal with an intensity that is 3 orders of magnitude larger due to the grating. Moreover, we demonstrate a field conversion efficiency for the third harmonic of up to ∼1% using a moderate field strength of ∼30 kV/cm. Finally, we show that harmonics beyond the third are enhanced even more strongly, allowing us to observe signatures of up to the ninth harmonic. Grating-graphene metamaterials thus constitute an outstanding platform for commercially viable, CMOS-compatible, room-temperature, chip-integrated, THz nonlinear conversion applications. ; K.-J.T. acknowledges funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 804349 (ERC StG CUHL) and financial support through the MAINZ Visiting Professorship. ICN2 was supported by the Severo Ochoa program from Spanish MINECO Grant No. SEV-2017-0706. Parts of this research were carried out at ELBE at the Helmholtz-Zentrum Dresden-Rossendorf e.V., a member of the Helmholtz Association. N.A., S.K., and I.I. acknowledge support from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 737038 (TRANSPIRE). X.J. acknowledges the support from the Max Planck Graduate Center with the Johannes Gutenberg-Universität Mainz (MPGC). ; Peer reviewed

Photonic beam has attracted massive researchers' attention from the time of invention in the earlier decades and would continue due to unimaginable characteristics that contributed potentially to reach the highest data transmission rate and remarkable bandwidth in addition to the less susceptible to the environmental parameters via hundreds of kilometers. This advantage gives to think about it to address the water cycle issue in the shortage water region such as Gulf countries. The proposal considers the controllable beam properties that could carry the evaporation gas to pass through the air pollution layers and complete the condensation process hence reinforces an increase in rainfall chances, and lead to reducing the desalination process as well cost-effectiveness. Accordingly, the photonics beam station could sense and analyze the pollution layer to make a proper decision based on the data variability. The paper takes into account the matter via suggesting a new model that accommodates the significant environmental parameters in the desert area particularly in Qatar which is severely prone to the water lake due to salinity and stark weather in addition to the oil and gas manufacturing, which add a heavy layer in the atmosphere. So, this proofing would help the government sector strikingly the meteorology, energy, and resources to mitigate the impact of water shortage and provide a technical solution that would reflect in the whole countries economy. The work also attention to the absorption phenomenon for the most significant available wavelengths such as 850,1330 and 1550 nm and the results demonstrated the lowest wavelength prone to absorption between 610 nm up to 700 nm and from 1550 nm until 1600 nm ; Citation: Elmutasim, I.E., Mohd, I.I., Bilal, K.H. (2021). Contemplation of the Photonics Beam to Complement the Water Cycle in Gulf Region, Journal of Scientific Technology and Engineering Research, 2(2): 15-21. DOI:10.5281/zenodo.5037867

THz communications systems at carrier frequencies above 200 GHz are the key to enable next-generation mobile communication networks with 100 Gbit/s wireless data rates. One of the key questions is, which carrier frequency generation technique will be the most suitable. This is currently addressed by two separate approaches, electronics-based and photonics-based. We present in this paper a truly microwave photonic approach that benefits from the main key features of each, bandwidth, tunability, stability and fiber compatibility from photonics and power handling capability from the electronics. It is based on a Photonic Local Oscillator (PLO), generating a 100 GHz frequency, fed into an electronic frequency multiplier. A high speed uni-travelling carrier photodiode (UTC-PD) provides the 100 GHz PLO for Schottky tripler diodes, generating 300 GHz signal. To feed the UTC-PD, we present a photonic integrated mode locked laser source. According to the simulations and measurements, the developed transmitter can produce a maximum of 12 μWof THz power at 280 GHz. ; This work has been supported by European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 642355 FiWiN5G, as well as by Spanish Ministerio de Economía y Competitividad through Programa Estatal de Investigación, Desarrollo e Inovación Orientada a los Retos de la Sociedad (grant iTWIT, TEC2016-76997-C3-3-R).

A system to interrogate photonic sensors based on a very weak fiber Bragg grating cascade fiber is presented and experimentally validated and dedicated to detecting the presence and location of a spot event. The distributed sensor proposed consists of a 5-m-long fiber, containing 500 9-mm-long Bragg gratings with a grating separation of 10.21 mm. The principle of operation is based on a technique used to analyze microwave photonics filters. The detection of spot events along the sensor is demonstrated with remarkable accuracy under 1 mm, using a photodetector and a modulator with a bandwidth of only 500 MHz. The simple proposed scheme is intrinsically robust against environmental changes and is easy to reconfigure. ; This work was supported in part by the Infraestructura FEDER UPVOV08-3E-008, by FEDER UPVOV10-3E-492, by the Spanish MCINN through Project TEC2011-29120-C05-05, by the Valencia Government through Ayuda Complementaria ACOMP/2013/146, by the grant of the program SANTIAGO GRISOLIA, and by the Research Excellency Award Program GVA PROMETEO 2013/012. ; Ricchiuti, AL.; Hervás Peralta, J.; Barrera Vilar, D.; Sales Maicas, S.; Capmany Francoy, J. (2014). Microwave photonics filtering technique for interrogating a very-weak fiber Bragg grating cascade sensor. IEEE Photonics Journal. 6(6). https://doi.org/10.1109/JPHOT.2014.2363443 ; S ; 6 ; 6

The luminescent hydrophobic composite films based on nanocellulose matrix with up-conversion SrF2 :Ho or CaF2 :Ho particles have been synthesized and studied by X-ray diffraction, electron microscopy and optical spectroscopy techniques. The size distributions of cellulose nanoparticles in homogeneous aqueous dispersions of cellulose nanocrystals (CNC), cellulose nanofibrils (CNF) and TEMPO-oxidized nanocellulose (TOCN) were determined. Flexible, durable, translucent composite films were obtained by molding from the said CNC/CNF or TOCN suspensions and up-conversion particles. Optical transmission, spectral-luminescent properties, surface morphology, degree of polymerization, structure and crystallinity index of nanocellulose, surface hydrophobization conditions of the said CNC/CNF or TOCN composite films have been determined. The manufactured up-conversion hydrophobic composite films can be utilized as potential photonics materials (in particular, materials for the visualization of near-infrared laser radiation), as luminescent labels, luminescent detectors, etc.

The United States government has something like 500 research and development laboratories. They include labs operated by the Department of Agriculture, the Department of Defense, Department of Commerce, Department of Energy and Department of Transportation, as well as national labs and labs of the Atomic Energy Commission. For a long time the government has wanted these labs to transfer technology to industry, especially in our post‐war world. Have they succeeded in this transfer?