Download or read book Real space Pseudopotential Calculations for the Electronic and Structural Properties of Nanostructures written by Jiaxin Han and published by . This book was released on 2010 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructures often possess unique properties, which may lead to the development of new microelectronic and optoelectronic devices. They also provide an opportunity to test fundamental quantum mechanical concepts such as the role of quantum confinement. Considerable effort has been made to understand the electronic and structural properties of nanostructures, but many fundamental issues remain. In this work, the electronic and structural properties of nanostructures are examined using several new computational methods. The effect of dimensional confinement on quantum levels is investigated for hydrogenated Ge 110 using the plane-wave density-functional-theory pseudopotential method. We present a real-space pseudopotential method for calculating the electronic structure of one-dimensional periodic systems such as nanowires. As an application of this method, we examine H-passivated Si nanowires. The band structure and heat of formation of the Si nanowires are presented and compared to plane wave methods. Our method is able to offer the same accuracy as the traditional plane wave methods, but offers a number of computational advantages such as the ability to handle large systems and a better ease of implementation for highly parallel platforms. Doping is important to many potential applications of nano-regime semiconductors. A series of first-principles studies are conducted on the P-doped Si 110 nanowires by the real-space pseudopotential methods. Nanowires of varied sizes and different doping positions are investigated. We calculate the binding energies of P atoms, band gaps of the wires, energetics of P atoms in different doping positions and core-level shift of P atoms. Defect wave functions of P atoms are also analyzed. In addition, we study the electronic properties of phosphorus-doped silicon 111 nanofilms using the real-space pseudopotential method. Nanofilms with varied sizes and different doping positions are investigated. We calculate the binding energies of P atoms, band gaps of the films, and energetics of P atoms in different doping positions. Quantum confinement effects are compared with P-doped Si nanocrystals and as well as nanowires. We simulate the nanofilm STM images with P defects in varied film depths, and make a comparison with the experimental measurement.

Download or read book First principles Calculations in Real space Formalism written by Kikuji Hirose and published by World Scientific. This book was released on 2005 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: With cutting-edge materials and minute electronic devices being produced by the latest nanoscale fabrication technology, it is essential for scientists and engineers to rely on first-principles (ab initio) calculation methods to fully understand the electronic configurations and transport properties of nanostructures. It is now imperative to introduce practical and tractable calculation methods that accurately describe the physics in nanostructures suspended between electrodes.This timely volume addresses novel methods for calculating electronic transport properties using real-space formalisms free from geometrical restrictions. The book comprises two parts: The first details the basic formalism of the real-space finite-difference method and its applications. This provides the theoretical foundation for the second part of the book, which presents the methods for calculating the properties of electronic transport through nanostructures sandwiched by semi-infinite electrodes.

Download or read book First principles Calculations In Real space Formalism Electronic Configurations And Transport Properties Of Nanostructures written by Kikuji Hirose and published by World Scientific. This book was released on 2005-01-19 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: With cutting-edge materials and minute electronic devices being produced by the latest nanoscale fabrication technology, it is essential for scientists and engineers to rely on first-principles (ab initio) calculation methods to fully understand the electronic configurations and transport properties of nanostructures. It is now imperative to introduce practical and tractable calculation methods that accurately describe the physics in nanostructures suspended between electrodes.This timely volume addresses novel methods for calculating electronic transport properties using real-space formalisms free from geometrical restrictions. The book comprises two parts: The first details the basic formalism of the real-space finite-difference method and its applications. This provides the theoretical foundation for the second part of the book, which presents the methods for calculating the properties of electronic transport through nanostructures sandwiched by semi-infinite electrodes./a

Download or read book Electronic Structure Calculations on Graphics Processing Units written by Ross C. Walker and published by John Wiley & Sons. This book was released on 2016-02-16 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electronic Structure Calculations on Graphics Processing Units: From Quantum Chemistry to Condensed Matter Physics provides an overview of computing on graphics processing units (GPUs), a brief introduction to GPU programming, and the latest examples of code developments and applications for the most widely used electronic structure methods. The book covers all commonly used basis sets including localized Gaussian and Slater type basis functions, plane waves, wavelets and real-space grid-based approaches. The chapters expose details on the calculation of two-electron integrals, exchange-correlation quadrature, Fock matrix formation, solution of the self-consistent field equations, calculation of nuclear gradients to obtain forces, and methods to treat excited states within DFT. Other chapters focus on semiempirical and correlated wave function methods including density fitted second order Møller-Plesset perturbation theory and both iterative and perturbative single- and multireference coupled cluster methods. Electronic Structure Calculations on Graphics Processing Units: From Quantum Chemistry to Condensed Matter Physics presents an accessible overview of the field for graduate students and senior researchers of theoretical and computational chemistry, condensed matter physics and materials science, as well as software developers looking for an entry point into the realm of GPU and hybrid GPU/CPU programming for electronic structure calculations.

Download or read book Real space Electronic Structure Methods for Modeling Nanowires and Atomic Force Microscopy Imaging written by Alex Jemyung Lee and published by . This book was released on 2016 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our group develops a pseudopotential-based electronic structure code constructed within first-principles density functional theory to study various problems in chemical engineering and condensed matter physics. One of the code's unique features is that it performs calculations on a real-space grid without using an explicit basis. This makes it particularly well-suited for examining localized systems with confined dimensionalities, such as nanostructures. In the dissertation we apply our code to the study of two main topics: germanium nanowires and atomic force microscopy simulations. First we examine how the electronic properties of germanium nanowires are affected by mechanical strain. We find that applying strain can drastically influence the transport properties of nanowires by inducing band crossings that change the nature of the band gap from direct to indirect, hampering carrier mobilities. In another project we take advantage of the real-space formalism for charged systems to devise a computationally efficient method to calculate accurate doping binding energies for nanowires. We demonstrate the method on phosphorus-doped germanium nanowires. The second focus of the dissertation is atomic force microscopy simulations. Atomic force microscopy is a powerful probe-based imaging technique that can be used to visualize and characterize chemical phenomena. However, the interpretation of experimental images is not well-understood. We develop a theoretical simulation method in order to better understand the fundamental physics behind the imaging mechanism. In one study, we clarify the mechanism for imaging hydrogen bonds. Experimental findings on certain organic oligomers have reported striking images showing what appear to be direct visualizations of intermolecular bonding. We apply our simulation technique to show that tip tilting is responsible for resolving these apparent hydrogen bonds. In another study, we examine the phenomenon of contrast inversion. We find that the key factor responsible for contrast inversion is the chemical reactivity of the tip. Theoretical imaging simulations such as these can be used to guide the experimental acquisition of images and to help characterize results.

Download or read book Real space Pseudopotential Calculations of the Ground state and Excited state Properties of Molecules and Clusters written by Marie Lopez del Puerto and published by . This book was released on 2008 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electronic and Structural Properties of Functional Nanostructures written by Teng Yang and published by . This book was released on 2009 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Magnetic Nanostructures written by D.J. Sellmyer and published by Springer Science & Business Media. This book was released on 2006-07-02 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced magnetic nanostructures is an emerging field in magnetism and nanotechnology, but the literature consists of a rich variety of original papers and parts of reviews and books whose scope is comparatively broad. This calls for a book with specific emphasis on state-of-the-art synthetic methods for fabricating, characterizing and theoretically modeling new magnetic nanostructures. This book is intended to provide a comprehensive overview of the present state of the field. Leading researchers world-wide have contributed a survey of their special ties to guide the reader through the exploding literature in nanomagnetic structures. The focus is on deliberately structured nanomagnets. It includes cluster assembled, self-organized and patterned thin films but excludes, for example, multilayered thin films. We target both industrial and academic researchers in magnetism and related areas, such as nanotechnology, materials science, and theoretical solid-state physics.

Download or read book Theoretical Modeling of Inorganic Nanostructures written by R. A. Evarestov and published by Springer Nature. This book was released on 2020-06-10 with total page 865 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the state of the art in the theoretical modeling of inorganic nanostructures. Extending the first edition, published in 2015, it presents applications to new nanostructured materials and theoretical explanations of recently discovered optical and thermodynamic properties of known nanomaterials. It discusses the developments in theoretical modeling of nanostructures, describing fundamental approaches such as symmetry analysis and applied calculation methods. The book also examines the theoretical aspects of many thermodynamic and the optical properties of nanostructures. The new edition includes additional descriptions of the theoretical modeling of nanostructures in novel materials such as the V2O5 binary oxide, ZnS, CdS, MoSSe and SnS2.

Download or read book Second Order Non linear Optics of Silicon and Silicon Nanostructures written by O. A. Aktsipetrov and published by CRC Press. This book was released on 2018-09-03 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theory and practice of the non-linear optics of silicon are inextricably linked with a variety of areas of solid state physics, particularly semiconductor physics. However, the current literature linking these fields is scattered across various sources and is lacking in depth. Second Order Non-linear Optics of Silicon and Silicon Nanostructures describes the physical properties of silicon as they apply to non-linear optics while also covering details of the physics of semiconductors. The book contains six chapters that focus on: The physical properties and linear optics of silicon Basic theoretical concepts of reflected second harmonics (RSH) The authors’ theory of the generation of RSH at the non-linear medium–linear medium interface An analytical review of work on the non-linear optics of silicon The results of non-linear optical studies of silicon nanostructures A theory of photoinduced electronic processes in semiconductors and their influence on RSH generation The book also includes methodological problems and a significant amount of reference data. It not only reflects the current state of research but also provides a single, thorough source of introductory information for those who are becoming familiar with non-linear optics. Second Order Non-linear Optics of Silicon and Silicon Nanostructures is a valuable contribution to the fields of non-linear optics, semiconductor physics, and microelectronics, as well as a useful resource for a wide range of readers, from undergraduates to researchers.

Download or read book Sustainable Materials for Next Generation Energy Devices written by Kuan Yew Cheong and published by Elsevier. This book was released on 2020-12-01 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sustainable Materials for Next Generation Energy Devices: Challenges and Opportunities presents the latest state-of-the-art knowledge and innovation related to environmentally-friendly functional materials that can be developed for, and employed in, producing a feasible next generation of energy storage and conversion devices. The book is broken up into three sections, covering Energy Storage, Energy Conversion and Advanced Concepts. It will be an important reference for researchers, engineers and students who want to gain extensive knowledge in green and/or sustainable functional materials and their applications. Provides a concise resource for readers interested in sustainable and green functional materials for energy conversion and storage devices Emphasizes sustainable and green concepts in the design of energy devices based on renewable functional materials Presents a survey of both the challenges and opportunities available for renewable functional materials in the development of energy devices

Download or read book Wave Propagation in Nanostructures written by Srinivasan Gopalakrishnan and published by Springer Science & Business Media. This book was released on 2013-09-10 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wave Propagation in Nanostructures describes the fundamental and advanced concepts of waves propagating in structures that have dimensions of the order of nanometers. The book is fundamentally based on non-local elasticity theory, which includes scale effects in the continuum model. The book predominantly addresses wave behavior in carbon nanotubes and Graphene structures, although the methods of analysis provided in this text are equally applicable to other nanostructures. The book takes the reader from the fundamentals of wave propagation in nanotubes to more advanced topics such as rotating nanotubes, coupled nanotubes, and nanotubes with magnetic field and surface effects. The first few chapters cover the basics of wave propagation, different modeling schemes for nanostructures and introduce non-local elasticity theories, which form the building blocks for understanding the material provided in later chapters. A number of interesting examples are provided to illustrate the important features of wave behavior in these low dimensional structures.

Download or read book Chemically Deposited Nanocrystalline Metal Oxide Thin Films written by Fabian I. Ezema and published by Springer Nature. This book was released on 2021-06-26 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book guides beginners in the areas of thin film preparation, characterization, and device making, while providing insight into these areas for experts. As chemically deposited metal oxides are currently gaining attention in development of devices such as solar cells, supercapacitors, batteries, sensors, etc., the book illustrates how the chemical deposition route is emerging as a relatively inexpensive, simple, and convenient solution for large area deposition. The advancement in the nanostructured materials for the development of devices is fully discussed.

Download or read book Conceptual Foundations of Materials written by and published by Elsevier. This book was released on 2006-09-20 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this Volume "Conceptual Foundations of Materials: A standard model for ground- and excited-state properties" is to present the fundamentals of electronic structure theory that are central to the understanding and prediction of materials phenomena and properties. The emphasis is on foundations and concepts. The Sections are designed to offer a broad and comprehensive perspective of the field. They cover the basic aspects of modern electronic structure approaches and highlight their applications to the structural (ground state, vibrational, dynamic and thermodynamic, etc.) and electronic (spectroscopic, dielectric, magnetic, transport, etc.) properties of real materials including solids, clusters, liquids, and nanostructure materials. This framework also forms a basis for studies of emergent properties arising from low-energy electron correlations and interactions such as the quantum Hall effects, superconductivity, and other cooperative phenomena. Although some of the basics and models for solids were developed in the early part of the last century by figures such as Bloch, Pauli, Fermi, and Slater, the field of electronic structure theory went through a phenomenal growth during the past two decades, leading to new concepts, understandings, and predictive capabilities for determining the ground- and excited-state properties of real, complex materials from first principles. For example, theory can now be used to predict the existence and properties of materials not previously realized in nature or in the laboratory. Computer experiments can be performed to examine the behavior of individual atoms in a particular process, to analyze the importance of different mechanisms, or just to see what happen if one varies the interactions and parameters in the simulation. Also, with ab initio calculations, one can determine from first principles important interaction parameters which are needed in model studies of complex processes or highly correlated systems. Each time a new material or a novel form of a material is discovered, electronic structure theory inevitably plays a fundamental role in unraveling its properties. Provides the foundations of the field of condensed matter physics An excellent supplementary text for classes on condensed matter physics/solid state physics Volume covers current work at the forefront Presentations are accessible to nonspecialists, with focus on underlying fundamentals

Download or read book Encyclopedia of Interfacial Chemistry written by and published by Elsevier. This book was released on 2018-03-29 with total page 5276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry, Seven Volume Set summarizes current, fundamental knowledge of interfacial chemistry, bringing readers the latest developments in the field. As the chemical and physical properties and processes at solid and liquid interfaces are the scientific basis of so many technologies which enhance our lives and create new opportunities, its important to highlight how these technologies enable the design and optimization of functional materials for heterogeneous and electro-catalysts in food production, pollution control, energy conversion and storage, medical applications requiring biocompatibility, drug delivery, and more. This book provides an interdisciplinary view that lies at the intersection of these fields. Presents fundamental knowledge of interfacial chemistry, surface science and electrochemistry and provides cutting-edge research from academics and practitioners across various fields and global regions

Download or read book Quantum Wells Wires and Dots written by Paul Harrison and published by John Wiley & Sons. This book was released on 2005-10-31 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum Wells, Wires and Dots Second Edition: Theoretical andComputational Physics of Semiconductor Nanostructures providesall the essential information, both theoretical and computational,for complete beginners to develop an understanding of how theelectronic, optical and transport properties of quantum wells,wires and dots are calculated. Readers are lead through a series ofsimple theoretical and computational examples giving solidfoundations from which they will gain the confidence to initiatetheoretical investigations or explanations of their own. Emphasis on combining the analysis and interpretation ofexperimental data with the development of theoretical ideas Complementary to the more standard texts Aimed at the physics community at large, rather than just thelow-dimensional semiconductor expert The text present solutions for a large number of realsituations Presented in a lucid style with easy to follow steps related toaccompanying illustrative examples

Download or read book Simulation of Transport in Nanodevices written by François Triozon and published by John Wiley & Sons. This book was released on 2016-11-22 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Linear current-voltage pattern, has been and continues to be the basis for characterizing, evaluating performance, and designing integrated circuits, but is shown not to hold its supremacy as channel lengths are being scaled down. In a nanoscale circuit with reduced dimensionality in one or more of the three Cartesian directions, quantum effects transform the carrier statistics. In the high electric field, the collision free ballistic transform is predicted, while in low electric field the transport remains predominantly scattering-limited. In a micro/nano-circuit, even a low logic voltage of 1 V is above the critical voltage triggering nonohmic behavior that results in ballistic current saturation. A quantum emission may lower this ballistic velocity.