Download or read book Synthesis and Characterization of Rare Earth Doped Wide Bandgap Materials written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been found that codopant impurities (O, C, F) can enhance the luminescence and efficiency of Si:Er, but only when introduced in the proper Er/Impurity ratio. While it has been shown that addition of elements such as C and O can enhance the IR emission from GaN:Er, there has as yet been no systematic investigation of the role of the concentration of these codopants in the luminescence and surface properties of the GaN films. In this work, the effect of C codoping introduced via CBr4 on the structural and optical properties of GaN:Er films grown on sapphire by gas source molecular beam epitaxy (GSMBE) has been investigated in an attempt to address these issues. The effect of post-growth annealing on PL intensity in the carbon-doped material has also been explored. Finally, Eu-doping of GaN has been investigated for potential use in red emitting devices.
Download or read book Fabrication and Characterization of Rare Earth Doped Wide Bandgap Semiconductors for Spectral Storage written by Mohamed Fawzy Aly and published by . This book was released on 2006 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: In magnesium sulfide, oxygen doped magnesium sulfide and calcium sulfides, europium centers occur in different spectral regions. Therefore, multi-layer thin film structures were fabricated to allow for higher density of spectral storage.
Download or read book Optical Characterization of Rare Earth doped Wide Band Gap Semiconductors written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive spectroscopic studies of Er implanted GaN and in-situ Er doped AlN and GaN prepared by metalorganic molecular beam epitaxy were carried out. Each investigated sample exhibited strong 1.54 um luminescence at room temperature. it was found, however, that the incorporation and excitation schemes of Er in III Nitrides are rather complex and strongly depend on the material synthesis. For example, it was observed that high oxygen and carbon concentrations in GaN:Er greatly enhance the 1.54 um Er(3+) PL intensity under below gap excitation. Photoluminescence excitation (PLE) studies revealed that oxygen/carbon introduces a broad below gap PLE band, which provides an efficient pathway for E(3+) excitation. Under above gap excitation, however, the absolute Er(3+) PL intensity from GaN:Er samples was greatly reduced and only a weak PL dependence on the oxygen and carbon concentration was observed. Pump intensity dependent E(3+) PL studies revealed that the Er(3+) excitation efficiency for above gap pumping is reduced by a factor of 30 compared to below gap pumping. Based on the efficient below gap Er excitation a novel hybrid InGaN/GaN:Er LED operating at 1.54 um was demonstrated. Questions concerning the overall efficiency of this novel hybrid LED need to be further addressed in the future. More materials engineering focusing on improvement in the Er excitation efficiency is necessary to optimize the 1.54 um E(3+) PL from GaN:Er for practical device applications.
Download or read book Rare Earth and Transition Metal Doping of Semiconductor Materials written by Volkmar Dierolf and published by Woodhead Publishing. This book was released on 2016-01-23 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rare Earth and Transition Metal Doping of Semiconductor Material explores traditional semiconductor devices that are based on control of the electron’s electric charge. This book looks at the semiconductor materials used for spintronics applications, in particular focusing on wide band-gap semiconductors doped with transition metals and rare earths. These materials are of particular commercial interest because their spin can be controlled at room temperature, a clear opposition to the most previous research on Gallium Arsenide, which allowed for control of spins at supercold temperatures. Part One of the book explains the theory of magnetism in semiconductors, while Part Two covers the growth of semiconductors for spintronics. Finally, Part Three looks at the characterization and properties of semiconductors for spintronics, with Part Four exploring the devices and the future direction of spintronics. Examines materials which are of commercial interest for producing smaller, faster, and more power-efficient computers and other devices Analyzes the theory behind magnetism in semiconductors and the growth of semiconductors for spintronics Details the properties of semiconductors for spintronics
Download or read book Synthesis and Characterization of Rare Earth Doped Novel Optical Materials and Their Potential Applications written by Madhab Pokhrel and published by . This book was released on 2013 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Rare Earth Based Ceramic Nanomaterials written by Sahar Zinatloo-Ajabshir and published by Elsevier. This book was released on 2022-01-15 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Rare Earth-Based Ceramic Nanomaterials focuses on recent advances related to preparation methods and applications of advanced rare earth-based ceramic nanomaterials. Different approaches for synthesizing rare earth-based ceramic nanomaterials are discussed, along with their advantages and disadvantages for applications in various fields. Sections cover rare earth-based ceramic nanomaterials like ceria and rare earth oxides (R2O3), rare earth vanadates, rare earth titanates, rare earth zirconates, rare earth stannates, rare earth-based tungstates, rare earth-based manganites, ferrites, cobaltites, nickelates, rare earth doped semiconductor nanomaterials, rare earth molybdates, rare earth-based nanocomposites, rare earth-based compounds for solar cells, and laser nanomaterials based on rare-earth compounds. Reviews the chemistry and processing of rare earth doped ceramic nanomaterials and their characteristics and applications Covers a broad range of materials, including ceria and rare earth oxides (R2O3), vanadates, titanates, zirconates, stannates, tungstates, manganites, ferrites, cobaltites, nickelates, rare earth doped semiconductor nanomaterials, rare earth molybdates, rare earth-based nanocomposites, rare earth-based compounds for solar cells, and laser nanomaterials based on rare-earth compounds Includes different approaches to synthesizing each family of rare earth-based ceramic nanomaterials, along with their advantages and disadvantages Provides green chemistry-based methods for the preparation of advanced rare earth-based ceramic nanomaterials
Download or read book Handbook on Synthesis Strategies for Advanced Materials written by A. K. Tyagi and published by Springer Nature. This book was released on 2021-10-22 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents state-of-the-art coverage of synthesis of advanced functional materials. Unconventional synthetic routes play an important role in the synthesis of advanced materials as many new materials are metastable and cannot be synthesized by conventional methods. This book presents various synthesis methods such as conventional solid-state method, combustion method, a range of soft chemical methods, template synthesis, molecular precursor method, microwave synthesis, sono-chemical method and high-pressure synthesis. It provides a comprehensive overview of synthesis methods and covers a variety of materials, including ceramics, films, glass, carbon-based, and metallic materials. Many techniques for processing and surface functionalization are also discussed. Several engineering aspects of materials synthesis are also included. The contents of this book are useful for researchers and professionals working in the areas of materials and chemistry.
Download or read book Bibliography written by Pierre Villars and published by Walter de Gruyter. This book was released on 2012-12-21 with total page 1827 pages. Available in PDF, EPUB and Kindle. Book excerpt: By browsing about 10 000 000 scientific articles of over 200 major journals mainly in a 'cover to cover approach' some 200 000 publications were selected. The extracted data is part of the following fundamental material research fields: crystal structures (S), phase diagrams (also called constitution) (C) and the comprehensive field of intrinsic physical properties (P). This work has been done systematically starting with the literature going back to 1900. The above mentioned research field codes (S, C, P) as well as the chemical systems investigated in each publication were included in the present work. The aim of the Inorganic Substances Bibliography is to provide researchers with a comprehensive compilation of all up to now published scientific publications on inorganic systems in only three handy volumes.
Download or read book SYNTHESIS AND CHARACTERIZATION OF TRIVALENT Er3 Tb3 DOPED WITH Sr2CeO4 PHOSPHOR written by Dr. Pradip Z. Zambare and published by Lulu.com. This book was released on 2017-03-13 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rare earth elements have had and still have a unique and important impact on our lives. The unfilled 4f electronic structure of the rare earth elements makes them have special properties in luminescence, magnetism and electronics, which could be used to develop many new materials for various applications such as phosphors, magnetic materials, hydrogen storage materials and catalysts [1]. Rare-earth-doped luminescent materials (i.e. phosphors) are known to emit at distinct and different wavelengths in the electromagnetic spectrum and have been extensively used in color cathode ray tubes (CRT), tri-phosphor fluorescent lamps, X-ray intensifying screens and recently developed vacuum mercury-free lamps, as well as various types of displays such as plasma display panels, field emission displays and projection TVs [2].
Download or read book Growth by Radio Frequency Sputtering and Characterisation of Rare Earth Doped Wide Bandgap Oxides written by Rajesh Pandiyan and published by . This book was released on 2013 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis reports the results of an experimental research on rare earth ion-doping effects on the structural, chemical, optical and near-infra-red photoluminescence properties of wide band gap oxide films. The aim of the work was to develop materials with good photoluminescence properties, which can be applied to increase the photovoltaic conversion efficiency of crystalline Si-based solar cells, through the increase of the most efficient and useful fraction of the solar spectrum which hits the cells, thanks to a photon frequency down-shifting process. Neodymium trivalent ion (Nd3+) was used as dopant of TiO2 and ZnO thin films. The films, with different Nd concentrations were grown onto quartz by RF plasma co-sputtering and annealed at different temperatures (400°-800°). Different film architectures were investigated for their photoluminescence properties. Structural changes such as phase transformation from anatase to rutile, internal strain building and lattice distortion due to Nd3+ incorporation in titania, correlated with optical changes, were evidenced. Exciting titania and zinc oxide matrices with optimal Nd concentrations, with ultra-violet (UV) light energies equal to or above their gap values resulted in an efficient frequency down-shifting from UV to near-infra-red emission. The joint study of the vibrational, chemical and structural properties of the doped films allows the understanding of the excitation energy transfer process between the matrix to the ion, where self-trapped excitons can be involved. To conclude this study, the doped films were tested as down-shifter layers onto a Si-solar cell where they gave promising results. They were also tested for their photoactivity with methylene blue, showing their inhibitor effect on the photo-degradation of this organic dye molecule.
Download or read book Materials Science in Photocatalysis written by Elisa I. Garcia Lopez and published by Elsevier. This book was released on 2021-08-15 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Science in Photocatalysis provides a complete overview of the different semiconductor materials, from titania to third-generation photocatalysts, examining the increasing complexity and novelty of the materials science in photocatalytic materials. The book describes the most recommended synthesis procedure for each of them and the suitable characterization techniques for determining the optical, structural, morphological, and physical-chemical properties. The most suitable applications of the photocatalysts are described in detail, as well as their environmental applications for wastewater treatment, gaseous effluents depollution, water splitting, CO2 ?xation, selective organic synthesis, coupling reactions, and other selective transformations under both UV light and visible-light irradiation. This book offers a useful reference for a wide audience from students studying chemical engineering and materials chemistry to experienced researchers working on chemical engineering, materials science, materials engineering, environment engineering, nanotechnology, and green chemistry. Includes a complete overview of the different semiconductor materials used as photocatalysts Describes methods of preparation and characterization of photocatalysts and their applications Examines new possibilities to prepare effective photocatalysts
Download or read book Synthesis and Atomic level Characterization of Rare Earth Oxide Nanoparticles with EELS and XAS written by Ashley Sara Harvey and published by . This book was released on 2005 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hybrid Organic Inorganic Perovskites written by Li Wei and published by John Wiley & Sons. This book was released on 2020-10-19 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybrid organic-inorganic perovskites (HOIPs) have attracted substantial interest due to their chemical variability, structural diversity and favorable physical properties the past decade. This materials class encompasses other important families such as formates, azides, dicyanamides, cyanides and dicyanometallates. The book summarizes the chemical variability and structural diversity of all known hybrid organic-inorganic perovskites subclasses including halides, azides, formates, dicyanamides, cyanides and dicyanometallates. It also presents a comprehensive account of their intriguing physical properties, including photovoltaic, optoelectronic, dielectric, magnetic, ferroelectric, ferroelastic and multiferroic properties. Moreover, the current challenges and future opportunities in this exciting field are also been discussed. This timely book shows the readers a complete landscape of hybrid organic-inorganic pervoskites and associated multifuctionalities.
Download or read book Materials for Optoelectronics written by Maurice Quillec and published by Springer Science & Business Media. This book was released on 1996-01-31 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optoelectronics ranks one of the highest increasing rates among the different industrial branches. This activity is closely related to devices which are themselves extremely dependent on materials. Indeed, the history of optoelectronic devices has been following closely that of the materials. KLUWER Academic Publishers has thus rightly identified "Materials for Optoelectronics" as a good opportunity for a book in the series entitled "Electronic Materials; Science and Technology". Although a sound background in solid state physics is recommended, the authors have confined their contribution to a graduate student level, and tried to define any concept they use, to render the book as a whole as self-consistent as possible. In the first section the basic aspects are developed. Here, three chapters consider semiconductor materials for optoelectronics under various aspects. Prof. G. E. Stillman begins with an introduction to the field from the point of view of the optoelectronic market. Then he describes how III-V materials, especially the Multi Quantum Structures meet the requirements of optoelectronic functions, including the support of microelectronics for optoelectronic integrated circuits. In chapter 2, Prof.
Download or read book Crystalline Rare Earth Doped Sesquioxide PLD films on alumina alpha alumina written by Sebastian Bär and published by Cuvillier Verlag. This book was released on 2004 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Semiconductor Science and Technology written by and published by Newnes. This book was released on 2011-01-28 with total page 3572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductors are at the heart of modern living. Almost everything we do, be it work, travel, communication, or entertainment, all depend on some feature of semiconductor technology. Comprehensive Semiconductor Science and Technology, Six Volume Set captures the breadth of this important field, and presents it in a single source to the large audience who study, make, and exploit semiconductors. Previous attempts at this achievement have been abbreviated, and have omitted important topics. Written and Edited by a truly international team of experts, this work delivers an objective yet cohesive global review of the semiconductor world. The work is divided into three sections. The first section is concerned with the fundamental physics of semiconductors, showing how the electronic features and the lattice dynamics change drastically when systems vary from bulk to a low-dimensional structure and further to a nanometer size. Throughout this section there is an emphasis on the full understanding of the underlying physics. The second section deals largely with the transformation of the conceptual framework of solid state physics into devices and systems which require the growth of extremely high purity, nearly defect-free bulk and epitaxial materials. The last section is devoted to exploitation of the knowledge described in the previous sections to highlight the spectrum of devices we see all around us. Provides a comprehensive global picture of the semiconductor world Each of the work's three sections presents a complete description of one aspect of the whole Written and Edited by a truly international team of experts
Download or read book 4th International Conference on Nanotechnologies and Biomedical Engineering written by Ion Tiginyanu and published by Springer Nature. This book was released on 2019-09-17 with total page 835 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers the proceedings of the 4th International Conference on Nanotechnologies and Biomedical Engineering, held on September 18-21, 2019, in Chisinau, Republic of Moldova. It continues the tradition of the previous conference proceedings, thus reporting on both fundamental and applied research at the interface between nanotechnologies and biomedical engineering. Topics include: developments in bio-micro/nanotechnologies and devices; biomedical signal processing; biomedical imaging; biomaterials for biomedical applications; biomimetics; bioinformatics and e-health, and advances in a number of related areas. The book offers a timely snapshot of cutting-edge, multidisciplinary research and developments in the field of biomedical and nano-engineering.
