Transport Properties Of Correlated Electron Systems In The Nanoscale

The goal of this dissertation is to understand the microscopic origin of metal-insulator transition (MIT) in strongly correlated electron systems. Two such systems, VO2 and V2O5 in their nanoscale form are investigated. Results from experimental studies of electrical transport properties and of Raman spectroscopic measurements from single nanowires of these systems across the MIT are presented. In the VO2 system, the doping and confinement effects of MIT on the individual W-doped VO2 nanowires are studied. The hysteretic and abrupt transitions in the temperature or in the electrical driven MIT are observed and studied. While increasing the W content, the pronouncedly decreasing rate ( - (48-56) K/at. % W) of the MIT transition temperature (Tc) and low activation energy (Ea100 meV) suggest a more complex phase domain nucleation in this quasi-1D system.^Also, while driving MIT by applying voltage across sample, the temperature dependence of threshold voltages (VsubTH/sub) suggests the charge ordering and Joule heating in these nanowires, respectively. To understand the role of structural phase during the MITs, the simultaneous electrical transport and Raman spectroscopic measurements across temperature- and voltage-driven phase transitions are performed. Our results indicate no intermediate structural phases are required to mediate the structural phase transition. Moreover, both MITs show the coexistence of monoclinic (Msub1/sub) and rutile (R) during the transitions. The implications of these results are discussed. In the Vsub2/subOsub5/sub system, two single-crystal vanadium oxide bronzes in their nanowire form, & beta;super, /super- Cusubx/subVsub2/subOsub5/sub and $delta; -Ksubx/subVsub2/subOsub5/sub, were studied.^The hysteretic temperature driven MIT ranging up to almost 5 orders of magnitude in both nanowires has not been previously seen in their bulk form. Furthermore, the above room temperature transition (Tsubc

In recent years there has been a huge increase in the research and development of nanoscale science and technology. Central to the understanding of the properties of nanoscale structures is the modeling of electronic conduction through these systems. This graduate textbook provides an in-depth description of the transport phenomena relevant to systems of nanoscale dimensions. In this textbook the different theoretical approaches are critically discussed, with emphasis on their basic assumptions and approximations. The book also covers information content in the measurement of currents, the role of initial conditions in establishing a steady state, and the modern use of density-functional theory. Topics are introduced by simple physical arguments, with particular attention to the non-equilibrium statistical nature of electrical conduction, and followed by a detailed formal derivation. This textbook is ideal for graduate students in physics, chemistry, and electrical engineering.

Having earned chemical accuracy and physical reality, quantum transport theory, which dates back to the Landauer theory in the mesoscopic physics field, is expanding its power over material science and chemistry, forming a new subject of non-equilibrium quantum transport theory for charge and heat at the nanoscale. This growing subject invites cross-disciplinary developments: for example, the local heating theory developed there was examined and applied to the self-heating problem in the field of semiconductor and nanoelectronic device physics . Considering this, a reprint book compiling key important papers into a single comprehensive volume is convenient and comprehensive. In this volume, 25 papers are collected and compiled into 4 sections. A brief introduction given in each section will help readers with various backgrounds. The book will appeal to anyone involved in charge and/or heat transport problems that are widely spread over various subjects in material science, chemistry, electrical engineering, and condensed matter physics.

The properties of strongly correlated electrons confined in two dimensions are a forefront area of modern condensed matter physics. In the past two or three decades, strongly correlated electron systems have garnered a great deal of scientific interest due to their unique and often unpredictable behavior. Two of many examples are the metallic state and the metal–insulator transition discovered in 2D semiconductors: phenomena that cannot occur in noninteracting systems. Tremendous efforts have been made, in both theory and experiment, to create an adequate understanding of the situation; however, a consensus has still not been reached. Strongly Correlated Electrons in Two Dimensions compiles and details cutting-edge research in experimental and theoretical physics of strongly correlated electron systems by leading scientists in the field. The book covers recent theoretical work exploring the quantum criticality of Mott and Wigner–Mott transitions, experiments on the metal–insulator transition and related phenomena in clean and dilute systems, the effect of spin and isospin degrees of freedom on low-temperature transport in two dimensions, electron transport near the 2D Mott transition, experimentally observed temperature and magnetic field dependencies of resistivity in silicon-based systems with different levels of disorder, and microscopic theory of the interacting electrons in two dimensions. Edited by Sergey Kravchenko, a prominent experimentalist, this book will appeal to advanced graduate-level students and researchers specializing in condensed matter physics, nanophysics, and low-temperature physics, especially those involved in the science of strong correlations, 2D semiconductors, and conductor–insulator transitions.

Recent advances in the fabrication of semiconductors have created almost un limited possibilities to design structures on a nanometre scale with extraordinary electronic and optoelectronic properties. The theoretical understanding of elec trical transport in such nanostructures is of utmost importance for future device applications. This represents a challenging issue of today's basic research since it requires advanced theoretical techniques to cope with the quantum limit of charge transport, ultrafast carrier dynamics and strongly nonlinear high-field ef fects. This book, which appears in the electronic materials series, presents an over view of the theoretical background and recent developments in the theory of electrical transport in semiconductor nanostructures. It contains 11 chapters which are written by experts in their fields. Starting with a tutorial introduction to the subject in Chapter 1, it proceeds to present different approaches to transport theory. The semiclassical Boltzmann transport equation is in the centre of the next three chapters. Hydrodynamic moment equations (Chapter 2), Monte Carlo techniques (Chapter 3) and the cellular au tomaton approach (Chapter 4) are introduced and illustrated with applications to nanometre structures and device simulation. A full quantum-transport theory covering the Kubo formalism and nonequilibrium Green's functions (Chapter 5) as well as the density matrix theory (Chapter 6) is then presented.

This is an agenda-setting and high-profile book that presents an authoritative and cutting-edge analysis of nanoscience and technology. The Oxford Handbook of Nanoscience and Technology provides a comprehensive and accessible overview of the major achievements in different aspects of this field. The Handbook comprises 3 volumes, structured thematically, with 25 chapters each. Volume I presents fundamental issues of basic physics, chemistry, biochemistry, tribology etc. of nanomaterials. Volume II focuses on the progress made with host of nanomaterials including DNA and protein based nanostructures. Volume III highlights engineering and related developments, with a focus on frontal application areas. All chapters are written by noted international experts in the field. The book should be useful for final year undergraduates specializing in the field. It should prove indispensable to graduate students, and serious researchers from academic and industrial sectors working in the field of Nanoscience and Technology from different disciplines including Physics, Chemistry, Biochemistry, Biotechnology, Medicine, Materials Science, Metallurgy, Ceramics, Information Technology as well as Electrical, Electronic and Computational Engineering.

Peterson's Graduate Programs in the Physical Sciences contains a wealth of information on colleges and universities that offer graduate work in Astronomy and Astrophysics, Chemistry, Geosciences, Marine Sciences and Oceanography, Meteorology and Atmospheric Sciences, and Physics. The institutions listed include those in the United States, Canada, and abroad that are accredited by U.S. accrediting bodies. Up-to-date information, collected through Peterson's Annual Survey of Graduate and Professional Institutions, provides valuable information on degree offerings, professional accreditation, jointly offered degrees, part-time and evening/weekend programs, postbaccalaureate distance degrees, faculty, students, degree requirements, entrance requirements, expenses, financial support, faculty research, and unit head and application contact information. As an added bonus, readers will find a helpful "See Close-Up" link to in-depth program descriptions written by some of these institutions. These Close-Ups offer detailed information about the physical sciences program, faculty members and their research, and links to the program or department's Web site. In addition, there are valuable articles on financial assistance and support at the graduate level and the graduate admissions process, with special advice for international and minority students. Another article discusses important facts about accreditation and provides a current list of accrediting agencies.

The book provides an accessible introduction to the principles of condensed matter physics with a focus on the nanosciences and device technologies. The basics of electronic, phononic, photonic, superconducting, optics, quantum optics, and magnetic properties are explored, and nanoscience and device materials are incorporated throughout the chapters. Many examples of the fundamental principles of condensed matter physics are taken directly from nanoscience and device applications. This book requires a background in electrodynamics, quantum mechanics, and statistical mechanics at the undergraduate level. It will be a valuable reference for advanced undergraduates and graduate students of physics, engineering, and applied mathematics. Features Contains discussions of the basic principles of quantum optics and its importance to lasers, quantum information, and quantum computation. Provides references and a further reading list to additional scientific literature so that readers can use the book as a starting point to then follow up with a more advanced treatment of the topics covered. Requires only a basic background in undergraduate electrodynamics, quantum mechanics, and statistical mechanics.

Transport Phenomena in Micro- and Nanoscale Functional Materials and Devices offers a pragmatic view on transport phenomena for micro- and nanoscale materials and devices, both as a research tool and as a means to implant new functions in materials. Chapters emphasize transport properties (TP) as a research tool at the micro/nano level and give an experimental view on underlying techniques. The relevance of TP is highlighted through the interplay between a micro/nanocarrier's characteristics and media characteristics: long/short-range order and disorder excitations, couplings, and in energy conversions. Later sections contain case studies on the role of transport properties in functional nanomaterials. This includes transport in thin films and nanostructures, from nanogranular films, to graphene and 2D semiconductors and spintronics, and from read heads, MRAMs and sensors, to nano-oscillators and energy conversion, from figures of merit, micro-coolers and micro-heaters, to spincaloritronics. Presents a pragmatic description of electrical transport phenomena in micro- and nanoscale materials and devices from an experimental viewpoint Provides an in-depth overview of the experimental techniques available to measure transport phenomena in micro- and nanoscale materials Features case studies to illustrate how each technique works Highlights emerging areas of interest in micro- and nanomaterial transport phenomena, including spintronics