194 research outputs found
Optical Frequency Domain Interferometry for the Characterization and Development of Complex and Tunable Photonic Integrated Circuits
[ES] Esta tesis aborda la caracterización de circuitos fotónicos integrados (PIC) usando interferometría óptica en el domino de las frecuencias (OFDI). OFDI tiene una implementación razonablemente simple e interroga al dispositivo bajo test (DUT) proporcionando su respuesta en el dominio del tiempo, en la que los distintos caminos ópticos seguidos por la luz se manifiestan en contribuciones que contienen información de posición, amplitud y fase. Junto con un "setup" OFDI construido en nuestros laboratorios y estructuras de test integradas que involucran anillos resonantes, interferómetros, etc., proponemos e implementamos técnicas para obtener parámetros ópticos cruciales tales como el índice de grupo, dispersión cromática, rotación de polarización y pérdidas de propagación en guías de onda. También para caracterizar acopladores ópticos. Se realizan evaluaciones directas de fase óptica en diferentes experimentos para, entre otras aplicaciones, caracterizar efectos de calor en chips. En la culminación de la tesis, se aborda la integración conjunta de los interferómetros de OFDI junto con el DUT, concibiéndolo como una estructura de caracterización integrada. El uso de guías de onda integradas proporciona una alta estabilidad y adaptación al DUT, además de un mecanismo inherente de compensación de la dispersión. Se realiza un análisis y prueba de concepto experimental caracterizando un "arrayed waveguide grating" en tecnología de nitruro de silicio. Seguidamente, se da un paso adelante proponiendo una arquitectura interferométrica de tres brazos novedosa que permite reducir la complejidad de la medida. Se lleva a cabo una validación experimental amplia usando distintos equipos de laboratorio, acoplamiento horizontal y vertical al chip, y diferentes DUTs en tecnologías de nitruro de silicio y "silicon-on-insulator".[CAT] Aquesta tesi aborda la caracterització de circuits fotònics integrats (PIC) usant interferometria òptica al domini de les freqüències (OFDI). OFDI té una implementació raonablement simple i interroga el dispositiu sota test (DUT) proporcionant la seva resposta en el domini del temps, en què els diferents camins òptics seguits per la llum es manifesten en contribucions que contenen informació de posició, amplitud i fase. Juntament amb un "setup" OFDI construït als nostres laboratoris i estructures de test integrades que involucren anells ressonants, interferòmetres, etc., proposem i implementem tècniques per obtenir paràmetres òptics crucials com ara l'índex de grup, dispersió cromàtica, rotació de polarització i pèrdues de propagació en guies d'ona. També per caracteritzar acobladors òptics. Es fan avaluacions directes de fase òptica en diferents experiments per, entre altres aplicacions, caracteritzar efectes de calor en xips. A la culminació de la tesi, s'aborda la integració conjunta dels interferòmetres d'OFDI juntament amb el DUT, concebent-ho com una estructura de caracterització integrada. L'ús de guies d'ona integrades proporciona una alta estabilitat i adaptació al DUT, a més d'un mecanisme inherent de compensació de la dispersió. Es realitza una anàlisi i prova de concepte experimental caracteritzant un "arrayed waveguide grating" en tecnologia de nitrur de silici. Seguidament, es fa un pas avant proposant una arquitectura interferomètrica de tres braços nova que permet reduir la complexitat de la mesura. Es du a terme una validació experimental àmplia usant diferents equips de laboratori, acoblament horitzontal i vertical al xip, i diferents DUTs en tecnologies de nitrur de silici i "silicon-on-insulator".[EN] This PhD thesis covers the characterization of complex photonic integrated circuits (PIC) by using Optical Frequency Domain Interferometry (OFDI). OFDI has a fairly simple implementation and interrogates the device under test (DUT) providing its time domain response, in which the different optical paths followed by light manifest in contributions with position, amplitude and phase information. Together with a working OFDI setup built in our laboratory and integrated test structures involving devices such as ring resonators, interferometers, etc., we propose and implement techniques to get crucial optical parameters such as waveguide group refractive index, chromatic dispersion, polarization rotation, and propagation loss. Also, to characterize optical couplers. Direct optical phase assessment is made in different experiments permitting, amongst others, the characterization of on-chip heat effects. In the culmination of the thesis, the co-integration of the OFDI interferometers with the DUT is addressed, conceiving it as an integrated characterization structure. The use of integrated waveguides provide high stability and adaptation to the DUT, as well as an inherent dispersion de-embedding mechanism. It is provided analysis and experimental proof of concept with an arrayed waveguide grating as DUT in a silicon nitride platform. A considerable leap forward is then taken by proposing a novel three-way interferometer architecture, reducing the measurement complexity. Wide experimental validation is carried out using different laboratory equipment, horizontal and vertical chip coupling, and different DUTs in silicon nitride and silicon-on-insulator.Bru Orgiles, LA. (2022). Optical Frequency Domain Interferometry for the Characterization and Development of Complex and Tunable Photonic Integrated Circuits [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181635TESI
Advanced and versatile interferometric technique for the characterization of photonic integrated devices
[EN] Adaptable and complex optical characterization of photonic integrated devices, permitting to unearth possible design and fabrication errors in the different workflow steps are highly desired in the community. Here, we propose a technique capable of resolving full optical amplitude and phase response, in both frequency and time domains, of a photonic integrated device. It relies on optical frequency domain interferometry and makes use of a novel integrated architecture; a 3-way interferometer enabling single input and single output detection. We derive the test structure design rules and provide extensive experimental validation in silicon nitride and silicon on insulator technologies, by testing relevant devices such as arrayed waveguide grating, Mach-Zehnder interferometers, and ring resonators. Horizontal and vertical chip coupling, different external setup arrangements, and the optical dispersion de-embedding inherent to the technique are demonstrated. Finally, we discuss why this characterization approach might lay the groundwork of a standard testing tool for photonic integrated devices.Ministerio de Economia y Competitividad (PTA2015-11309-I, TEC2015-69787-REDT PIC4TB, TEC201680385-P SINXPECT); Ministerio de Ciencia, Innovacion y Universidades (PID2019-110877GB-I00 BHYSINPICS); Generalitat Valenciana (GVA PROMETEO 2017/103).Bru-Orgiles, LA.; Pastor Abellán, D.; Muñoz, P. (2021). Advanced and versatile interferometric technique for the characterization of photonic integrated devices. Optics Express. 29(22):36503-36515. https://doi.org/10.1364/OE.435683S3650336515292
Multi-parameter estimation of high-Q silicon rich nitride resonators using optical frequency domain reflectometry
Many linear and nonlinear optics applications rely on micro-resonators (MRRs) with carefully designed dispersion and coupling rate coefficients. These parameters are however challenging to measure for MRRs based on high-confinement optical waveguides. In this paper, we report on the use of optical frequency domain reflectometry (OFDR) for the measurement of group velocity dispersion (GVD), coupling coefficients and round-Trip loss, in high-Q (Q i ∼ 0.3
7 10 6 ) silicon-rich nitride MRRs. This technique allows for retrieving the GVD coefficients, intrinsic losses and coupling coefficients for each transverse mode in the resonator, thus providing very valuable feed-back information from experiments to the design flow step
Textile Reinforced Mortars (TRM) tensile behavior after high temperature exposure
Although one of the main advantages of Textile Reinforced Mortars (TRM) is their non-combustible character, their behavior against fire or high temperatures has not been sufficiently studied at present. This work analyzes the behavior of different commercial systems containing inorganic mortars and fabric reinforcements based on glass, carbon and basalt fibers, subjected to different temperature levels. To characterize the mechanical response of the different systems, non-destructive tests have been carried out to determine the dynamic modulus of elasticity of the different materials, and subsequent destructive tests to determine their strength and stress-strain relationship. For this purpose, the TRM coupons have been subjected to uniaxial tensile tests and the deformations have been monitored using LVDT (Linear Variable Displacement Transducer) sensors and DIC (Digital Image Correlation), in order to evaluate cracking patterns and failure modes. The results show, in general terms, that the mechanical capacity of these materials is seriously compromised at temperatures in the order of 400 to 600 °C, which can easily be reached during a fire inside a building. Therefore, it can be concluded that although these systems are erroneously perceived as fire resistant in many cases, they may require additional protection depending on the specific use for which they are intended.The authors would like to acknowledge Mapei Spain S.A. for the materials supplied in this work. This research has been funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-100
Copia literal de la ejecutoria de nobleza del Cuerpo de Artillería ... otorgada por el rey de armas de S. M. don Alfonso XIII, D. Luis Rubio de Ganga Yarzo y Bru ...
Tit tomado de la cub.Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201
Designed folding of pseudopeptides: the transformation of a configurationally driven preorganization into a stereoselective multicomponent macrocyclization
The efficient synthesis of large-ring pseudopeptidic macrocycles through a multicomponent [2+2] reductive amination reaction is described. The reaction was entirely governed by the structural information contained in the corresponding open-chain pseudopeptidic bis(amidoamine) precursors, which have a rigid (R,R)-cyclohexane-1,2-diamine moiety. A remarkable match/mismatch relationship between the configurations of the chiral centers of the cyclic diamine and those of the peptidic frame was observed. The macrocyclic tetraimine intermediates have been studied in detail by NMR spectroscopy, circular dichroism (CD), and molecular modeling, and the results support the appropriate preorganization induced by the match combination of the chiral centers. We have also synthesized the corresponding open-chain bis(imine) model compounds. The structural studies (NMR spectroscopy, CD, modeling) of these systems showed an intrinsically lower reactivity of the mismatch combination, even when the product of the reaction was acyclic. In addition, a synergistic effect between the two chiral substructures for the correct folding of the molecules was observed. Finally, X-ray analysis of the HCl salt of one of the macrocycles showed an interesting pattern; the macrocyclic rings stack in columnar aggregates leaving large interstitial channels filled with water-solvated chloride anion
Emotional intelligence measures: a systematic review
Emotional intelligence (EI) refers to the ability to perceive, express, understand, and manage emotions. Current research indicates that it may protect against the emotional burden experienced in certain professions. This article aims to provide an updated systematic review of existing instruments to assess EI in professionals, focusing on the description of their characteristics as well as their psychometric properties (reliability and validity). A literature search was conducted in Web of Science (WoS). A total of 2761 items met the eligibility criteria, from which a total of 40 different instruments were extracted and analysed. Most were based on three main models (i.e., skill-based, trait-based, and mixed), which differ in the way they conceptualize and measure EI. All have been shown to have advantages and disadvantages inherent to the type of tool. The instruments reported in the largest number of studies are Emotional Quotient Inventory (EQ-i), Schutte Self Report-Inventory (SSRI), Mayer-Salovey-Caruso Emotional Intelligence Test 2.0 (MSCEIT 2.0), Trait Meta-Mood Scale (TMMS), Wong and Law's Emotional Intelligence Scale (WLEIS), and Trait Emotional Intelligence Questionnaire (TEIQue). The main measure of the estimated reliability has been internal consistency, and the construction of EI measures was predominantly based on linear modelling or classical test theory. The study has limitations: we only searched a single database, the impossibility of estimating inter-rater reliability, and non-compliance with some items required by PRISMA
Crystal structures of the HCl salts of pseudopeptidic macrocycles display ‘‘knobs into holes’’ hydrophobic interactions between aliphatic side chains
The crystal structures of three HCl salts of pseudopeptidic macrocycles show a H-bonding tubular stack of the rings, where the amino acidic side chains (Val, Leu, Ile) display an inter-columnar “knobs into holes” hydrophobic interaction patter
Quantum walk on a cylinder
International audienceWe consider the two-dimensional alternate quantum walk on a cylinder. We concentrate on the study of the motion along the open dimension, in the spirit of looking at the closed coordinate as a small or " hidden " extra dimension. If one starts from localized initial conditions on the lattice, the dynamics of the quantum walk that is obtained after tracing out the small dimension shows the contribution of several components which can be understood from the study of the dispersion relations for this problem. In fact, these components originate from the contribution of the possible values of the quasimomentum in the closed dimension. In the continuous space-time limit, the different components manifest as a set of Dirac equations, with each quasimomentum providing the value of the corresponding mass. We briefly discuss the possible link of these ideas to the simulation of high-energy physical theories that include extra dimensions. Finally, entanglement between the coin and spatial degrees of freedom is studied, showing that the entanglement entropy clearly overcomes the value reached with only one spatial dimension
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