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 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 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 Growth Characterization and Luminescence and Optical Properties of Rare earth Elements and Transition Metals Doped in Wide Bandgap Nitride Semiconductors written by Muhammad Maqbool and published by . This book was released on 2005 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Processing of Wide Band Gap Semiconductors written by S. J. Pearton and published by Cambridge University Press. This book was released on 2013-01-15 with total page 593 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wide bandgap semiconductors, made from such materials as GaN, SiC, diamond, and ZnSe, are undergoing a strong resurgence in recent years, principally because of their direct bandgaps, which give them a huge advantage over the indirect gap Sic As an example, more than 10 million blue LEDs using this technology are sold each month, and new, high brightness (15 lumens per watt), long-life white LEDs are under development with the potential to replace incandescent bulbs in many situations. This book provides readers with a broad overview of this rapidly expanding technology, bringing them up to speed on new discoveries and commercial applications. It provides specific technical applications of key processes such as laser diodes, LEDs, and very high temperature electronic controls on engines, focusing on doping, etching, oxidation passivation, growth techniques and more.
Download or read book The Role of Defect Complexes in the Magneto Optical Properties of Rare Earth Doped Gallium Nitride written by Brandon Mitchell and published by . This book was released on 2014 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wide band gap semiconductors doped with rare earth ions (RE) have shown great potential for applications in optoelectronics, photonics, and spintronics. The 1.54mum Erbium (Er) emission has been extensively utilized in optical fiber communications, and Europium (Eu) is commonly used as a red color component for LEDs and fluorescence lamps. For the realization of spintronic-type devices, a dilutely doped semiconductor that exhibits room temperature ferromagnetic behavior would be desirable. Such behavior has been observed in GaN:Er. Furthermore, it was demonstrated that strain may play an important role in the control of this ferromagnetism; however, this requires further investigation.
Download or read book Proceedings of the 4th International Symposium on Materials and Sustainable Development written by Abdelbaki Benmounah and published by Springer Nature. This book was released on 2020-10-24 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the proceedings of the 4th International Symposium on Materials and Sustainable Development ISMSD2019 (CIMDD2019), will include a 3-day Conference (12 - 14 November). Organized by the Research Unit: Materials, Processes and Environment and M'hamed Bougara University of Boumerdes (Algeria) in partnership with University of Reims - Champagne-Ardenne (France), this symposium follows the success of CIMDD 2013-2015-2017 and continues the traditions of the highly successful series of International Conferences on the materials, processes and Environment. The Symposium will provide a unique topical forum to share the latest results of the materials and sustainable development research in Algeria and worldwide.
Download or read book III Nitride Semiconductors written by Hongxing Jiang and published by CRC Press. This book was released on 2002-06-28 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of a comprehensive overview of fundamental optical properties of III-nitride semiconductors. All optoelectronic applications based on III-nitrides are due to their unique optical properties and characterizations of III-nitrides. Much information, which is critical to the design and improvement of optoelectronic devices based on III-nitrides has been obtained in the last several years. This is the first of a two part Volume in the series Optoelectronic Properties of Semiconductors and Superlattices. Part I begins with time-resolved studies of semiconductors and moves on to the emphasis on time-resolved photoluminescence of nitride materials and device technology and focuses on Raman studies and properties of III Nitrides. This unique volume provides a comprehensive review and introduction of the defects and structural properties of GaN and related compounds. This would be excellent for newcomers to the field and is a stimulus to further advances for experienced researchers.III-Nitride Semiconductors: Optical Properties Part I combines contributions from active experts in the field with diverse backgrounds. This book provides a very important step in advancing the state of research and device development in the field of III-nitride materials.
Download or read book State of the Art Program on Compound Semiconductors XXXVIII and Wide Bandgap Semiconductors for Photonic and Electronic Devices and Sensors III written by Edward B. Stokes and published by The Electrochemical Society. This book was released on 2003 with total page 292 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 Introduction to the Electronic Properties of Materials written by David C. Jiles and published by CRC Press. This book was released on 2017-12-21 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electronic materials provide the basis for many high tech industries that have changed rapidly in recent years. In this fully revised and updated second edition, the author discusses the range of available materials and their technological applications. Introduction to the Electronic Properties of Materials, 2nd Edition presents the principles of the behavior of electrons in materials and develops a basic understanding with minimal technical detail. Broadly based, it touches on all of the key issues in the field and offers a multidisciplinary approach spanning physics, electrical engineering, and materials science. It provides an understanding of the behavior of electrons within materials, how electrons determine the magnetic thermal, optical and electrical properties of materials, and how electronic properties are controlled for use in technological applications. Although some mathematics is essential in this area, the mathematics that is used is easy to follow and kept to an appropriate level for the reader. An excellent introductory text for undergraduate students, this book is a broad introduction to the topic and provides a careful balance of information that will be appropriate for physicists, materials scientists, and electrical engineers.
Download or read book Recent Trends in Materials and Devices written by Vinod Kumar Jain and published by Springer. This book was released on 2016-10-20 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the proceedings of the International Conference on Recent Trends in Materials and Devices, which was conceived as a major contribution to large-scale efforts to foster Indian research and development in the field in close collaboration with the community of non-resident Indian researchers from all over the world. The research articles collected in this volume - selected from among the submissions for their intrinsic quality and originality, as well as for their potential value for further collaborations - document and report on a wide range of recent and significant results for various applications and scientific developments in the areas of Materials and Devices. The technical sessions covered include photovoltaics and energy storage, semiconductor materials and devices, sensors, smart and polymeric materials, optoelectronics, nanotechnology and nanomaterials, MEMS and NEMS, as well as emerging technologies.
Download or read book Air Force Research Resum s written by and published by . This book was released on with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Luminescence written by Jagannathan Thirumalai and published by BoD – Books on Demand. This book was released on 2016-11-10 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to give readers a broad review of topical worldwide advancements in theoretical and experimental facts, instrumentation and practical applications erudite by luminescent materials and their prospects in dealing with different types of luminescence like photoluminescence, electroluminescence, thermo-luminescence, triboluminescence, bioluminescence design and applications. The additional part of this book deals with the dynamics, rare-earth ions, photon down-/up-converting materials, luminescence dating, lifetime, bioluminescence microscopical perspectives and prospects towards the basic research or for more advanced applications. This book is divided into four main sections: luminescent materials and their associated phenomena; photo-physical properties and their emerging applications; thermoluminescence dating: from theory to applications, and bioluminescence perspectives and prospects. Individual chapters should serve the broad spectrum of common readers of diverse expertise, layman, students and researchers, who may in this book find easily elucidated fundamentals as well as progressive principles of specific subjects associated with these phenomena. This book was created by 14 contributions from experts in different fields of luminescence and technology from over 20 research institutes worldwide.
Download or read book Quantum Efficiency in Complex Systems Part II From Molecular Aggregates to Organic Solar Cells written by and published by Academic Press. This book was released on 2011-11-23 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise that this tradition will be maintained and even expanded. Reflecting the truly interdisciplinary nature of the field that the series covers, the volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in modern industry. Written and edited by internationally renowned experts Relevant to a wide readership: physicists, chemists, materials scientists, and device engineers in academia, scientific laboratories and modern industry
Download or read book Solid State Lasers and Applications written by Alphan Sennaroglu and published by CRC Press. This book was released on 2017-12-19 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: Because of the favorable characteristics of solid-state lasers, they have become the preferred candidates for a wide range of applications in science and technology, including spectroscopy, atmospheric monitoring, micromachining, and precision metrology. Presenting the most recent developments in the field, Solid-State Lasers and Applications focuses on the design and applications of solid-state laser systems. With contributions from leading international experts, the book explores the latest research results and applications of solid-state lasers as well as various laser systems. The beginning chapters discuss current developments and applications of new solid-state gain media in different wavelength regions, including cerium-doped lasers in the ultraviolet range, ytterbium lasers near 1μm, rare-earth ion-doped lasers in the eye-safe region, and tunable Cr2+:ZnSe lasers in the mid-infrared range. The remaining chapters study specific modes of operation of solid-state laser systems, such as pulsed microchip lasers, high-power neodymium lasers, ultrafast solid-state lasers, amplification of femtosecond pulses with optical parametric amplifiers, and noise characteristics of solid-state lasers. Solid-State Lasers and Applications covers the most important aspects of the field to provide current, comprehensive coverage of solid-state lasers.
