Download or read book Optoelectronic and Structure Properties of Diluted Magnetic Semiconductor Based on ZnO Nanorods written by 劉宗維 and published by . This book was released on 2014 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ZnO and Their Hybrid Nano Structures written by Gaurav Sharma and published by Materials Research Forum LLC. This book was released on 2023-06-05 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: ZnO and its hybrid nanostructures have unique optical, physical and chemical properties. The book covers recent trends in processing techniques and applications. Topics include solar cells, photo-voltaic devices, fuel cells, uv filters, lasers, light-emitting diodes, photo-detectors, spin-tronic devices, magnetic semiconductors, nano-generators, piezotronics, photo-catalytic applications against harmful organic pollutants like dyes, heavy metals, antibiotics, and sensors such as bio sensors, chemical sensors, gas sensors. Keywords: ZnO, Nano ZnO, Point Defects, Magnetic Semiconductors, Hybrid Nanostructures, Cell Applications, Nanoadsorbant for Heavy Metal Removals, Diagnostics, ZnO Nano-Carriers, ZnO Thin Films Fabrication.

Download or read book Zinc Oxide based Diluted Magnetic Semiconductors written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: During my graduate research I have synthesized materials known as diluted magnetic semiconductors (DMS) as epitaxial thin film structures using the process of pulsed laser deposition (PLD). These materials are envisioned to be of importance in the emerging field of spintronics where the charge as well as the spin of the charge carriers can be combined to yield unique functionalities to yield novel devices including, on-chip memories, ultra-low power devices etc. The material of interest in this dissertation was zinc oxide, a wide bandgap optoelectronic semiconductor. ZnO has a bandgap of 3.3 eV. It is an ideal candidate for spintronics applications, because Zn is the last of the first row transition metals, which leads to pretty high solubility of transition metals such as Co, Mn and V in ZnO. In a diluted magnetic semiconductor a fraction of the host atoms is substituted by the transition metal dopant ion. We have found that we can synthesize very high quality, single phase and single crystalline Zn(TM)O thin films on basal plane sapphire single crystals (a-Al2O3). We have analyzed the magnetic properties of the three systems of ZnVO, ZnCoO and ZnMnO and found that ZnCoO and ZnMnO exhibit ferromagnetic ordering up to room temperature, when synthesized under high vacuum. In these conditions, the samples have a reasonable concentration of point defects which drive ZnO to n-type conductivity. By a combination of insitu and exsitu variation of parameters we have been able to tune the electronic and magnetic properties of these systems. From these studies we conclude that the main mechanism of magnetic ordering in these DMS materials is through a combination of defect related carrier induced exchange and bound magnetic polaron exchange. Device structures were fabricated using the as deposited samples to study the possibility of spin injection through semiconductors. We have observed that at low temperatures we see a considerable effect from this phenomenon in a m.

Download or read book Structural and Magnetic Properties of Zno Doped with Mn and Co written by Vijay Kumar Sharma and published by LAP Lambert Academic Publishing. This book was released on 2010-12 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: ZnO based Diluted magnetic semiconductors (DMSs) have attracted broad interest for their promise functionalities in spintronics based devices. In this book, we explored the effect of different synthesis techniques (solid-state, sol-gel and chemical vapor deposition (CVD) methods) and synthesis parameters (sintering temperature, doping concentration, annealing atmosphere) on the structural and magnetic properties of TM (Mn, Co) doped ZnO. The effect of Al/Sb codoping on the magnetic properties of ZnMnO and ZnCoO were studied. We also explored the structural, optical and magnetic properties of nanowires and nanorods of Mn doped ZnO for their potential in spintronics based devices. From the experimental results presented in this book, it is concluded that defects like oxygen vacancies, zinc vacancies etc. in the samples are important for room temperature ferromagnetism in ZnO based DMSs.

Download or read book Metal Oxides for Optoelectronics and Optics Based Medical Applications written by Suresh Sagadevan and published by Elsevier. This book was released on 2022-07-01 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Oxides for Optoelectronics and Optics-based Medical Applications reviews recent advances in metal oxides and their mechanisms for optoelectronic, photoluminescent and medical applications. In addition, the book examines the integration of key chemistry concepts with nanoelectronics that can improve performance in a diverse range of applications. Sections place a strong emphasis on synthesis processes that can improve the metal oxides' physical properties and the reflected surface chemical changes that can impact their performance in various devices like light-emitting diodes, luminescence materials, solar cells, etc. Finally, the book discusses the challenges associated with the handling and maintenance of metal oxides crystalline properties. This book will be suitable for academics and those working in R&D in industry looking to learn more about cheaper and more effective methods to produce metal oxides for use in the fields of electronics, photonics, biophotonics and engineering. - Reviews the latest advances in the utilization of metal oxide materials in photonics, optoelectronics and optics-based medical applications - Considers the most relevant synthesis strategies for the development of high-performing metal oxide-based devices - Addresses a wide range of metal oxides including photonic crystals, fibers, metastructures, glasses, and more

Download or read book Investigations of Structural Electrical Optical and Magnetic Properties of P and N type ZnO based Diluted Magnetic Semiconductor written by 李榮銓 and published by . This book was released on 2011 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dilute Magnetic Semiconductors Based on Gan and Zno written by Tom Kammermeier and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2010-05 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two wide band gap dilute magnetic semiconductors (DMS) Gd: GaN and Co: ZnO are among the most favored materials for spintronic applications. Despite intense research efforts during the last years, the origin of the magnetic order is still under debate. This work reports structural and magnetic investigations on these DMS materials employing several complementary techniques. The X-ray linear dichroism (XLD) has been used to gain element-specific insight into the local structure of dopants and cations. X-ray diffraction (XRD) has resulted in information about the global structural properties. Magnetic characterization by superconducting quantum interference device (SQUID) has been complemented by electron spin resonance (ESR) and X-ray magnetic circular dichroism (XMCD). This compilation of different techniques has yield new insight in the complex magnetic behavior of these wide band gap dilute magnetic semiconductor

Download or read book Nanostructured Metal Oxides and Devices written by M. K. Jayaraj and published by Springer Nature. This book was released on 2020-04-16 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book primarily covers the fundamental science, synthesis, characterization, optoelectronic properties, and applications of metal oxide nanomaterials. It discusses the basic aspects of synthetic procedures and fabrication technologies, explains the related experimental techniques and also elaborates on the current status of nanostructured oxide materials and related devices. Two major aspects of metal oxide nanostructures – their optical and electrical properties – are described in detail. The first five chapters focus on the optical characteristics of semiconducting materials, especially metal oxides at the nanoscale. The following five chapters discuss the electrical properties observed in metal oxide-based semiconductors and the status quo of device-level developments in a variety of applications such as sensors, transistors, dilute magnetic semiconductors, and dielectric materials. The basic science and mechanism behind the optoelectronic phenomena are explained in detail, to aid readers interested in the structure–property symbiosis in semiconducting nanomaterials. In short, the book offers a valuable reference guide for researchers and academics in the areas of material science and semiconductor technology, especially nanophotonics and electronics.

Download or read book Relationship Between Structure and Magnetic Behaviour in ZnO Based Systems written by Clara Guglieri Rodríguez and published by Springer. This book was released on 2015-06-03 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work studies the magnetic behavior of ZnO nanoparticles capped with different organic molecules and showing room-temperature ferromagnetism (RTFM). Of particular significance is the combination of element-specific X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) techniques, which demonstrates the intrinsic occurrence of RTFM in these systems and indicates that it is not related to the 3-D states of the metallic cation but is relayed along the conduction band of the semiconductor. The discovery of room-temperature ferromagnetism (RTFM) in semiconductors holds great promise in future spintronics technologies. Further results presented here include O K-edge XMCD studies, which demonstrate that the oxygen ions have a ferromagnetic response in these ZnO-based systems, providing the first direct support for claims regarding the appearance of oxygen ferromagnetism in oxide semiconductors at the nanoscale.

Download or read book Structural Electronic and Magnetic Properties of Diluted Magnetic Semiconductors Based on Transition Metals Doped Zinc Oxide written by Bakhtiar Ul Haq and published by . This book was released on 2014 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spectroscopic Ellipsometry written by Harland G. Tompkins and published by Momentum Press. This book was released on 2015-12-16 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ellipsometry is an experimental technique for determining the thickness and optical properties of thin films. It is ideally suited for films ranging in thickness from sub-nanometer to several microns. Spectroscopic measurements have greatly expanded the capabilities of this technique and introduced its use into all areas where thin films are found: semiconductor devices, flat panel and mobile displays, optical coating stacks, biological and medical coatings, protective layers, and more. While several scholarly books exist on the topic, this book provides a good introduction to the basic theory of the technique and its common applications. The target audience is not the ellipsometry scholar, but process engineers and students of materials science who are experts in their own fields and wish to use ellipsometry to measure thin film properties without becoming an expert in ellipsometry itself.

Download or read book First Principle Vs Experimental Design of Diluted Magnetic Semiconductors written by Omar Mounkachi and published by Nova Science Publishers. This book was released on 2018-10 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent discoveries have given rise to a new class of electronics known as "spin electronics or spintronics," which uses the electron spin rather than its charge to create polarized currents. Spintronics is currently experiencing an extraordinary development with the manufacture of nanoscale devices based on ferromagnetic materials and semiconductors. Their applications are numerous, ranging from recording, electronics, and optoelectronics to quantum information. Spintronics is a new generation of electronics that has brought and continues to bring a lot of progress to information storage; this is due to the discovery of new materials with new functionalities and multiple applications. The discovery of giant magnetoresistance (GMR) in 1988 by Albert Fert and Peter Grünberg (receiver of the Nobel Prize in Physics in 2007) is considered a starting point of spintronics. GMR is based on the variation of the electric current in the presence of a magnetic field. The spintronics has made important contributions to the miniaturization desired for electronics; it uses nanometric components for processing and storing information. However, the limits of miniaturization on a nanometric scale are known, and it is imperative to develop new ways and new materials to exceed those limits. The most desired properties for these materials are high spin polarization, modular magnetic properties by an electric field and a long lifetime of the spin polarization. Among the new promising materials, we cite the following: Diluted magnetic semiconductors, which give new magnetic properties of conventional semiconductors, functional oxides (including the semi-metals and multiferroic metals) and organic semiconductors. The main theoretical challenge in this area is to understand how the macroscopic magnetic behavior observed results from interactions of a large number of degrees of microscopic freedom. In these systems the disorder is an essential parameter of magnetic phenomena, and due to random locations of impurity atoms it can lead to a total physical difference from the observed absence. There has been considerable recent advances in the design of these materials as diluted magnetic semiconductors (DMS, or diluted magnetic semiconductors), and a number of semiconductors were investigated as II-VI group and III-V group doped compounds, with transition metals substituting their original cations. There are several different theoretical approaches to study these magnetic materials. The ab-initio approach starts from the Schrödinger equation to simulate a given material. Such an approach is essential to determine the parameters and microscopic properties of such a system. In this book, the authors analyzed the electronic structure of magnetic semiconductors diluted in the case of ZnO, GaN, SnO2, TiO2, MgH2, EuO and EuN doped RENs (RE=GdN, DyN and HoN). The authors focused on magnetic, optical and exchange mechanisms which control the ferromagnetism in these systems. The purpose of this book is to propose some ideas to answer the most important question in material science for semiconductor spintronics, primarily considering how room-temperature ferromagnetism in DMS can be realized. Additionally, the correlation between first principle and experimental design to see how properties of yet-to-be-synthesized materials can be predicted is discussed.

Download or read book Novel Diluted Magnetic Semiconductor Materials Based on Zinc Oxide written by Deepayan Chakraborti and published by . This book was released on 2007 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: Cu doped ZnO, Thin Film Epitaxy, Structure-Property Correlation, Ferromagnetism, Spintronic, Magnetoresistance.

Download or read book Nanocrystalline Materials written by Sie-Chin Tjong and published by Elsevier. This book was released on 2006-06-23 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocrystalline materials with new functionalities show great promise for use in industrial applications - such as reinforcing fillers in novel polymer composites – and substantial progress has been made in the past decade in their synthesis and processing. However, there are several issues that need to be addressed to develop these materials further. Among these, exploration of novel methods for the large-scale synthesis of low cost self-assembled nanostructures is a challenging research topic. Accordingly, there has emerged a demand to study their synthesis-structure-property relationships in order to understand the fundamental concepts underlying the observed physical and mechanical properties.With contributions from leading experts, this book describes the fundamental theories and concepts that illustrate the complexity of the problem in developing novel nanocrystalline materials. It reviews the most up-to-date progress in the synthesis, microstructural characterization, physical and mechanical behavior, and application of nanomaterials.* Investigates the synthesis, characterisation and properties of a huge variety of nanocrystalline materials, and their applications in industry * Keeps the prominent challenges in nanomaterials fabrication at the forefront while offering the most up-to-date scientific findings

Download or read book Optical Properties and Applications of Semiconductors written by Inamuddin and published by CRC Press. This book was released on 2022-07-18 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductors with optical characteristics have found widespread use in evolving semiconductor photovoltaics, where optical features are important. The industrialization of semiconductors and their allied applications have paved the way for optical measurement techniques to be used in new ways. Due to their unique properties, semiconductors are key components in the daily employed technologies in healthcare, computing, communications, green energy, and a range of other uses. This book examines the fundamental optical properties and applications of semiconductors. It summarizes the information as well as the optical characteristics and applicability of semiconductors through an in-depth review of the literature. Accomplished experts in the field share their knowledge and examine new developments. FEATURES Comprehensive coverage of all types of optical applications using semiconductors Explores relevant composite materials and devices for each application Addresses the optical properties of crystalline and amorphous semiconductors Describes new developments in the field and future potential applications Optical Properties and Applications of Semiconductors is a comprehensive reference and an invaluable resource for engineers, scientists, academics, and industry R&D teams working in applied physics.

Download or read book Novel Diluted Magnetic Semiconductor Materials based on Zinc Oxide written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary aim of this work was to develop a ZnO based diluted magnetic semiconductor (DMS) materials system which displays ferromagnetism above room temperature and to understand the origin of long-range ferromagnetic ordering in these systems. Recent developments in the field of spintronics (spin based electronics) have led to an extensive search for materials in which semiconducting properties can be integrated with magnetic properties to realize the objective of successful fabrication of spin-based devices. For these devices we require a high efficiency of spin current injection at room temperature. Diluted magnetic semiconductors (DMS) can serve this role, but they should not only display room temperature ferromagnetism (RTFM) but also be capable of generating spin polarized carriers. Transition metal doped ZnO has proved to be a potential candidate as a DMS showing RTFM. The origin of ferromagnetic ordering in ZnO is still under debate. However, the presence of magnetic secondary phases, composition fluctuations and nanoclusters could also explain the observation of ferromagnetism in the DMS samples. This encouraged us to investigate Cu-doped(+ ư spin in the 2+ valence state) ZnO system as a probable candidate exhibiting RTFM because neither metallic Cu nor its oxides (Cu2O or CuO) are ferromagnetic. The role of defects and free carriers on the ferromagnetic ordering of Cu-doped ZnO thin films was studied to ascertain the origin of ferromagnetism in this system. A novel non-equilibrium Pulsed Laser Deposition technique has been used to grow high quality epitaxial thin films of Cu:ZnO and (Co, Cu):ZnO on c-plane Sapphire by domain matching epitxay. Both the systems showed ferromagnetic ordering above 300K but Cu ions showed a much stronger ferromagnetic ordering than Co, especially at low concentrations (1-2 %) of Cu where we realized near 100% polarization. But, the incorporation of Cu resulted in a 2-order of magnitude rise in the resistivity from 10-1 t.

Download or read book Structure and Properties of 3d Transition Metal Doped ZnO written by Venkaiah Malapati and published by LAP Lambert Academic Publishing. This book was released on 2014-08-27 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: ZnO based semiconductors as transparent electrodes have given wide range of applications in optoelectronic devices due to their wide band gap replacing the conventional GaN semiconductors. This book is the compilation of the work of Venkaiah Malapati which deals with the synthesis and characterization of an interesting room temperature undoped and 3d transition metal doped ZnO thin films by rf magnetron sputtering. this work addresses the following three major questions... (1) what is the effect of working gas pressure on the properties of undoped and Mn, Fe and Mn-Fe co-doped ZnO thin films. Here, the effect of argon and oxygen gas pressure studied undoped and Mn and Fe doped thin films studied. This book includes a systematic study of structure, morphology, optical, mechanical and magnetic properties of undoped Mn, Fe doped ZnO thin films studied. This book should be useful to readers in enhancing their knowledge about thin film preparation and their characterization.