Download or read book Etude optique de la dynamique des interactions lectroniques dans des nanotubes de carbone written by Sébastien Berger and published by . This book was released on 2007 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette thèse est consacrée à l'étude expérimentale des propriétés électroniques des nanotubes de carbone par des techniques de spectroscopie de photoluminescence. Le travail a d'abord consisté en la préparation et la caractérisation d'échantillons de nanotubes de carbone isolés les uns des autres dans une suspension de surfactant. Ils présentent alors de la luminescence. Intégrés ensuite dans un gel, ils sont adaptés aux températures entre 10 et 300 K. le premier volet d'expériences a concerné la spectroscopie de luminescence en régime stationnaire. Les mesures sur des ensembles macroscopiques permettent d'identifier les classes de chiralité présentes et mettent en évidence divers phénomènes de couplage des nanotubes entre eux et à leur environnement. Grâce à un montage de microscopie confocale, on a en outre étudié la luminescence d'un nanotube unique. On s'affranchit ainsi de l'inhomogénéité de l'échantillon, comme le montrent les faibles largeurs de raies (moins de 1 meV à 10 K) et les phénomènes de diffusion spectrale et de clignotement observés à l'échelle de la seconde. Le second volet d'expériences est consacré à la spectroscopie de photoluminescence résolue en temps à l'échelle picoseconde, sur des ensembles de nanotubes. On mesure la dynamique de recombinaison des excitations élémentaires (excitons), sur 3 ordres de grandeur de variation, dans les chiralités (9,4) et (10,2). L'évolution du temps de vie (300 ps à 10 K, 50 ps à 300 K) et de l'intensité de la luminescence (présentant un maximum à 50 K) donne des informations sur la structure des états excitoniques. On estime en particulier qu'il existe un niveau noir 4 meV en dessous de l'état luminescent.
Download or read book Graphene and Carbon Nanotubes written by Ermin Malic and published by John Wiley & Sons. This book was released on 2013-04-12 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: A first on ultrafast phenomena in carbon nanostructures like graphene, the most promising candidate for revolutionizing information technology and communication The book introduces the reader into the ultrafast nanoworld of graphene and carbon nanotubes, including their microscopic tracks and unique optical finger prints. The author reviews the recent progress in this field by combining theoretical and experimental achievements. He offers a clear theoretical foundation by presenting transparently derived equations. Recent experimental breakthroughs are reviewed. By combining both theory and experiment as well as main results and detailed theoretical derivations, the book turns into an inevitable source for a wider audience from graduate students to researchers in physics, materials science, and electrical engineering who work on optoelectronic devices, renewable energies, or in the semiconductor industry.
Download or read book Photophysics of Carbon Nanotubes Interfaced with Organic and Inorganic Materials written by Igor A. Levitsky and published by Springer Science & Business Media. This book was released on 2012-12-22 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photophysics of Carbon Nanotubes Interfaced with Organic and Inorganic Materials describes physical, optical and spectroscopic properties of the emerging class of nanocomposites formed from carbon nanotubes (CNTs) interfacing with organic and inorganic materials. The three main chapters detail novel trends in photophysics related to the interaction of light with various carbon nanotube composites from relatively simple CNT/small molecule assemblies to complex hybrids such as CNT/Si and CNT/DNA nanostructures. The latest experimental results are followed up with detailed discussions and scientific and technological perspectives to provide a through coverage of major topics including: -Light harvesting, energy conversion, photoinduced charge separation and transport in CNT based nanohybrids -CNT/polymer composites exhibiting photoactuation; and -Optical spectroscopy and structure of CNT/DNA complexes. Including original data and a short review of recent research, Photophysics of Carbon Nanotubes Interfaced with Organic and Inorganic Materials makes this emerging field of photophysics and its applications available to academics and professionals working with carbon nanotube composites in fundamental and applied fields
Download or read book Interaction entre les nanotubes de carbone et leur environnement physico chimique written by Fabien Vialla and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette thèse est consacrée à l'étude expérimentale par spectroscopie de photoluminescence de nanotubes de carbone nus et fonctionnalisés. Les nanotubes étant formés exclusivement d'atomes de surface, leurs propriétés optiques peuvent être grandement altérées, mais aussi contrôlées, par interaction avec l'environnement physico-chimique. Un dispositif de microscopie confocale à l'échelle de l'objet unique et à température cryogénique est développé pour l'étude de la luminescence de nanotubes déposés sur substrat. La variété des profils spectraux observés est interprétée en terme d'un couplage entre excitons localisés et phonons acoustiques unidimensionnels dont le spectre peut être altéré aux basses énergies. Ce mécanisme explique notamment l'observation originale de raies très fines, de largeur inférieure à 500 μeV. La fonctionnalisation non-covalente des nanotubes par des molécules de colorants (porphyrines) introduit une nouvelle voie d'excitation optique par un transfert d'énergie très efficace. Le suivi physico-chimique de la réaction d'adsorption nous informe sur la couverture et l'affinité des molécules sur les nanotubes. Une étude de photoluminescence sur composés uniques résolue en polarisation montre une forte anisotropie du transfert d'énergie gouvernée par des effets d'antenne à proximité du nanotube. Enfin, le colorant peut être utilisé comme cellule d'absorption de référence pour évaluer la section efficace d'absorption des nanotubes. Une nette évolution avec l'angle chiral de l'espèce est notamment observée pour l'absorption à la résonance optique S22.
Download or read book Etude de la dynamique des tats excit s des nanotubes du carbone mono paroi written by Bertrand Kei Yuma and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce travail analyse la formation d'états liés par interaction coulombienne d'excitons dans un ensemble de nanotubes de carbone de chiralité (6,5) en solution. Sous l'action d'une impulsion laser de forte intensité, une grande densité d'excitons est formée dans le nanotube et conduit à la formation d'état de trion et de biexciton. Les mécanismes physiques responsables de la photogénération de ces états ont été analysés dans le cadre de cette thèse. Ces travaux sont effectués à l'aide d'une expérience pompe-sonde dans laquelle le faisceau sonde est un continuum de lumière blanche permettant ainsi l'observation simultanée des états d'exciton, de trion et de biexciton. Cela conduit à l'obtention des énergies de liaison des différentes contributions excitoniques. En outre la dynamique de ces états excitoniques a aussi pu être obtenue avec une résolution temporelle de l'ordre de la centaine de femtosecondes.
Download or read book Dynamique t rahertz des nanotubes de carbone written by Matthieu Baillergeau and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le développement de circuits mesoscopiques avec une architecture hybride cette dernière décennie a permis d'étudier l'interaction lumière matière dans son aspect fondamental avec des photons dans le régime micro-ondes. Ces développements permettent aujourd'hui d'étudier cette interaction dans le domaine terahertz, gamme spectrale s'étendant de 0.1 THz à 10 THz (0.4 meV-41,3 meV). L'apparition de sources performantes et de méthodes de spectroscopie efficaces telles que la spectroscopie dans le domaine temporel sont des outils utilisables pour l'étude de l'interaction lumière matière dans ce domaine spectral. Dans ce travail de thèse, nous avons développé un outil afin d'étudier cette interaction dans son aspect le plus fondamental composé d'un nanotube de carbone en régime de boîte quantique et d'une cavité térahertz. Le nanotube de carbone est un élément d'autant plus adapté que sa structure électronique est régie par des énergies dont la fréquence équivalente se situe dans le terahertz. La cavité térahertz est un "split ring resonator". Le travail s'est décomposé en deux aspects, avec dans un premier temps le développement d'un banc de spectroscopie térahertz large bande (0.3 THz-20 THz) dans le domaine temporel pour l'étude des résonateurs. En utilisant un procédé original de contrôle du front d'onde d'émission de l'antenne, nous démontrons que le champ térahertz est focalisé en limite de diffraction ce qui ouvre la possibilité d'étudier des résonateurs uniques. Dans un second temps, des mesures de transport électronique ont été effectuées afin de mettre en évidence un couplage entre le résonateur et la boîte quantique. Un couplage avec un mode bosonique est observé. La conductance de ces états est modulée par la source de photons utilisée dans cette étude. Cependant, l'énergie du mode est inférieure à celle observée par les mesures de spectroscopie ne permettant pas de conclure de manière définitive sur l'origine de ce mode.
Download or read book Magnetism and Superconductivity written by Laurent-Patrick Levy and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: This up-to-date work presents a modern vision of magnetism and superconductivity covering both microscopic and phenomenological aspects. The basic information is illustrated with the help of current research topics such as the quantum Hall effect or mesoscopic aspects of superconductivity.
Download or read book Optical Properties Of Graphene written by Rolf Binder and published by World Scientific. This book was released on 2016-11-11 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive state-of-the-art overview of the optical properties of graphene. During the past decade, graphene, the most ideal and thinnest of all two-dimensional materials, has become one of the most widely studied materials. Its unique properties hold great promise to revolutionize many electronic, optical and opto-electronic devices. The book contains an introductory tutorial and 13 chapters written by experts in areas ranging from fundamental quantum mechanical properties to opto-electronic device applications of graphene.
Download or read book ICREEC 2019 written by Ahmed Belasri and published by Springer Nature. This book was released on 2020-06-10 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.
Download or read book Quantum Transport written by Yuli V. Nazarov and published by Cambridge University Press. This book was released on 2009-05-28 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum transport is a diverse field, sometimes combining seemingly contradicting concepts - quantum and classical, conduction and insulating - within a single nanodevice. Quantum transport is an essential and challenging part of nanoscience, and understanding its concepts and methods is vital to the successful fabrication of devices at the nanoscale. This textbook is a comprehensive introduction to the rapidly developing field of quantum transport. The authors present the comprehensive theoretical background, and explore the groundbreaking experiments that laid the foundations of the field. Ideal for graduate students, each section contains control questions and exercises to check readers' understanding of the topics covered. Its broad scope and in-depth analysis of selected topics will appeal to researchers and professionals working in nanoscience.
Download or read book Flexoelectricity in Liquid Crystals written by Agnes Buka and published by World Scientific. This book was released on 2013 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book intends to give a state-of-the-art overview of flexoelectricity, a linear physical coupling between mechanical (orientational) deformations and electric polarization, which is specific to systems with orientational order, such as liquid crystals. Chapters written by experts in the field shed light on theoretical as well as experimental aspects of research carried out since the discovery of flexoelectricity. Besides a common macroscopic (continuum) description the microscopic theory of flexoelectricity is also addressed. Electro-optic effects due to or modified by flexoelectricity as well as various (direct and indirect) measurement methods are discussed. Special emphasis is given to the role of flexoelectricity in pattern-forming instabilities. While the main focus of the book lies in flexoelectricity in nematic liquid crystals, peculiarities of other mesophases (bent-core systems, cholesterics, and smectics) are also reviewed. Flexoelectricity has relevance to biological (living) systems and can also offer possibilities for technical applications. The basics of these two interdisciplinary fields are also summarized.
Download or read book Dynamic Behavior of Materials Volume 1 written by Bo Song and published by Springer. This book was released on 2015-10-23 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic Behavior of Materials, Volume 1 represents the first of nine volumes of technical papers presented at the Society for Experimental Mechanics SEM 15th International Congress & Exposition on Experimental and Applied Mechanics, held at Costa Mesa, California, June 8-11, 2015. The full set of proceedings also includes volumes on: Challenges in Mechanics of Time Dependent Materials, Advancement of Optical Methods in Experimental Mechanics, Experimental and Applied Mechanics 16th International Symposium on MEMS and Nanotechnology, 5th International Symposium on the Mechanics of Biological Systems and Materials, International Symposium on the Mechanics of Composite and Multi-functional Materials, Fracture, Fatigue, Failure and Damage Evolution; and Residual Stress, Thermomechanics & Infrared Imaging, Hybrid Techniques and Inverse Problems.
Download or read book ZnO Thin Films written by Paolo Mele and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc oxide (ZnO) is an n-type semiconductor with versatile applications such as optical devices in ultraviolet region, piezoelectric transducers, transparent electrode for solar cells and gas sensors. This book "ZnO Thin Films: Properties, Performance and Applications" gives a deep insight in the intriguing science of zinc oxide thin films. It is devoted to cover the most recent advances and reviews the state of the art of ZnO thin films applications involving energy harvesting, microelectronics, magnetic devices, photocatalysis, photovoltaics, optics, thermoelectricity, piezoelectricity, electrochemistry, temperature sensing. It serves as a fundamental information source on the techniques and methodologies involved in zinc oxide thin films growth, characterization, post-deposition plasma treatments and device processing. This book will be invaluable to the experts to consolidate their knowledge and provide insight and inspiration to beginners wishing to learn about zinc oxide thin films.
Download or read book Electron Paramagnetic Resonance Spectroscopy written by Patrick Bertrand and published by Springer Nature. This book was released on 2020-02-03 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although originally invented and employed by physicists, electron paramagnetic resonance (EPR) spectroscopy has proven to be a very efficient technique for studying a wide range of phenomena in many fields, such as chemistry, biochemistry, geology, archaeology, medicine, biotechnology, and environmental sciences. Acknowledging that not all studies require the same level of understanding of this technique, this book thus provides a practical treatise clearly oriented toward applications, which should be useful to students and researchers of various levels and disciplines. In this book, the principles of continuous wave EPR spectroscopy are progressively, but rigorously, introduced, with emphasis on interpretation of the collected spectra. Each chapter is followed by a section highlighting important points for applications, together with exercises solved at the end of the book. A glossary defines the main terms used in the book, and particular topics, whose knowledge is not required for understanding the main text, are developed in appendices for more inquisitive readers.
Download or read book Risk Assessment in the Process Industries written by Robin Turney and published by IChemE. This book was released on 1996 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this updated and amplified edition, Dr Pitblado answers the crucial questions of risk analysis: what can go wrong?; what are the effects and consequences?; and how often will it happen'.
Download or read book Inorganic Chemical Biology written by Gilles Gasser and published by John Wiley & Sons. This book was released on 2014-06-23 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding, identifying and influencing the biological systems are the primary objectives of chemical biology. From this perspective, metal complexes have always been of great assistance to chemical biologists, for example, in structural identification and purification of essential biomolecules, for visualizing cellular organelles or to inhibit specific enzymes. This inorganic side of chemical biology, which continues to receive considerable attention, is referred to as inorganic chemical biology. Inorganic Chemical Biology: Principles, Techniques and Applications provides a comprehensive overview of the current and emerging role of metal complexes in chemical biology. Throughout all of the chapters there is a strong emphasis on fundamental theoretical chemistry and experiments that have been carried out in living cells or organisms. Outlooks for the future applications of metal complexes in chemical biology are also discussed. Topics covered include: • Metal complexes as tools for structural biology • IMAC, AAS, XRF and MS as detection techniques for metals in chemical biology • Cell and organism imaging and probing DNA using metal and metal carbonyl complexes • Detection of metal ions, anions and small molecules using metal complexes • Photo-release of metal ions in living cells • Metal complexes as enzyme inhibitors and catalysts in living cells Written by a team of international experts, Inorganic Chemical Biology: Principles, Techniques and Applications is a must-have for bioinorganic, bioorganometallic and medicinal chemists as well as chemical biologists working in both academia and industry.
