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Avadh Saxena
Avadh B. Saxena is an American physicist and currently the Group Leader of Physics of Condensed Matter and Complex Systems Group (T-4) at Los Alamos National Laboratory, New Mexico, United States. His contributions cover a range of topics including phase transitions, functional materials, topological defects such as solitons and skyrmions, and Non-Hermitian quantum mechanics. Saxena completed his PhD at the Temple University in 1986 (advisor: James D. Gunton). Subsequently, he held a joint postdoc position at the Materials Research Lab at Penn State (with Gerhard R. Barsch) and Cornell University (with James A. Krumhansl). In 1990 he came to Los Alamos National Laboratory as a visiting scientist/consultant to the Theoretical Division (with Alan R. Bishop), and in 1993 became a Technical Staff Member. In January 2006 he assumed the Deputy Group Leader position of the Condensed Matter and Statistical Physics Group (formerly T-11) and since January 2009 he is the Group Leader o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensed Matter Physics
Condensed matter physics is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases which arise from electromagnetic forces between atoms. More generally, the subject deals with "condensed" phases of matter: systems of many constituents with strong interactions between them. More exotic condensed phases include the superconducting phase exhibited by certain materials at low temperature, the ferromagnetic and antiferromagnetic phases of spins on crystal lattices of atoms, and the Bose–Einstein condensate found in ultracold atomic systems. Condensed matter physicists seek to understand the behavior of these phases by experiments to measure various material properties, and by applying the physical laws of quantum mechanics, electromagnetism, statistical mechanics, and other theories to develop mathematical models. The diversity of systems and phenomena available for study makes condensed matter phy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsukuba
is a city located in Ibaraki Prefecture, Japan. , the city had an estimated population of 244,528 in 108,669 households and a population density of 862 persons per km². The percentage of the population aged over 65 was 20.3%. The total area of the city is . It is known as the location of the , a planned science park developed in the 1960s. Geography Tsukuba is located in southern Ibaraki Prefecture, approximately 50 kilometers from central Tokyo and about 40 kilometers from Narita International Airport. Mount Tsukuba, from which the city takes its name is located in the northern part of the city. Except for the area around Mount Tsukuba, the city is a part of the Kantō Plain with an altitude of 20 to 30 meters. Mountains: Mount Tsukuba, Mount Hokyo. Rivers: Kokai River, Sakura River, Higashiyata River, Nishiyata River, Ono River, Hanamuro River, Inari River. Parks: The city has more of 100 parks and green areas to relax. Different parks are connected by pedestrian w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moore's Law
Moore's law is the observation that the number of transistors in a dense integrated circuit (IC) doubles about every two years. Moore's law is an observation and projection of a historical trend. Rather than a law of physics, it is an empirical relationship linked to gains from experience in production. The observation is named after Gordon Moore, the co-founder of Fairchild Semiconductor and Intel (and former CEO of the latter), who in 1965 posited a doubling every year in the number of components per integrated circuit, and projected this rate of growth would continue for at least another decade. In 1975, looking forward to the next decade, he revised the forecast to doubling every two years, a compound annual growth rate (CAGR) of 41%. While Moore did not use empirical evidence in forecasting that the historical trend would continue, his prediction held since 1975 and has since become known as a "law". Moore's prediction has been used in the semiconductor industry to g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonlinear System
In mathematics and science, a nonlinear system is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, biologists, physicists, mathematicians, and many other scientists because most systems are inherently nonlinear in nature. Nonlinear dynamical systems, describing changes in variables over time, may appear chaotic, unpredictable, or counterintuitive, contrasting with much simpler linear systems. Typically, the behavior of a nonlinear system is described in mathematics by a nonlinear system of equations, which is a set of simultaneous equations in which the unknowns (or the unknown functions in the case of differential equations) appear as variables of a polynomial of degree higher than one or in the argument of a function which is not a polynomial of degree one. In other words, in a nonlinear system of equations, the equation(s) to be solved cannot be written as a linear combination of the un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topology
In mathematics, topology (from the Greek language, Greek words , and ) is concerned with the properties of a mathematical object, geometric object that are preserved under Continuous function, continuous Deformation theory, deformations, such as Stretch factor, stretching, Twist (mathematics), twisting, crumpling, and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself. A topological space is a set (mathematics), set endowed with a structure, called a ''Topology (structure), topology'', which allows defining continuous deformation of subspaces, and, more generally, all kinds of continuity (mathematics), continuity. Euclidean spaces, and, more generally, metric spaces are examples of a topological space, as any distance or metric defines a topology. The deformations that are considered in topology are homeomorphisms and homotopy, homotopies. A property that is invariant under such deformations is a topological property. Basic exampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geometry
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is called a ''geometer''. Until the 19th century, geometry was almost exclusively devoted to Euclidean geometry, which includes the notions of point, line, plane, distance, angle, surface, and curve, as fundamental concepts. During the 19th century several discoveries enlarged dramatically the scope of geometry. One of the oldest such discoveries is Carl Friedrich Gauss' ("remarkable theorem") that asserts roughly that the Gaussian curvature of a surface is independent from any specific embedding in a Euclidean space. This implies that surfaces can be studied ''intrinsically'', that is, as stand-alone spaces, and has been expanded into the theory of manifolds and Riemannian geometry. Later in the 19th century, it appeared that geometries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Functional Materials
''Advanced Functional Materials'' is a peer-reviewed scientific journal, published by Wiley-VCH. Established in February 2001, the journal began to publish monthly in 2002 and moved to 18/year in 2006, biweekly in 2008, and weekly in 2013. It has been published under other titles since 1985. See LCCN in infobox. Library of Congress. September 2010. Scope Coverage of this journal encompasses all topics pertaining to materials science. Topical coverage includes photovoltaics, organic electronics, carbon materials, nanotechnology, liquid crystals, magnetic materials, surfaces and interfaces, and biomaterials. Publishing formats include original research papers, feature articles and highlights. History It was established in 2001 by Peter Gregory, the Editor of ''Advanced Materials'', when the Wiley journal ''Advanced Materials for Optics and Electronics'' (starting in 1992) was discontinued; the volume numbering continued, however. ''Advanced Functional Materials'' is the sister jou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetism
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particles give rise to a magnetic field, which acts on other currents and magnetic moments. Magnetism is one aspect of the combined phenomena of electromagnetism. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt, and nickel and their alloys. The rare-earth metals neodymium and samarium are less common examples. The prefix ' refers to iron because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, Fe3O4. All substances exhibit some type of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charge Transport Mechanisms
Charge transport mechanisms are theoretical models that aim to quantitatively describe the electric current flow through a given medium. Theory Crystalline solids and molecular solids are two opposite extreme cases of materials that exhibit substantially different transport mechanisms. While in atomic solids transport is ''intra''-molecular, also known as band transport, in molecular solids the transport is ''inter''-molecular, also known as hopping transport. The two different mechanisms result in different charge mobilities. In disordered solids, disordered potentials result in weak localization effects (traps), which reduce the mean free path, and hence the mobility, of mobile charges. Carrier recombination also decreases mobility. Starting with Ohm's law and using the definition of conductivity, it is possible to derive the following common expression for current as a function of carrier mobility μ and applied electric field E: :I=GV=\sigma\fracV=\sigma AE=en\mu AE The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vibration
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin ''vibrationem'' ("shaking, brandishing"). The oscillations may be periodic function, periodic, such as the motion of a pendulum—or random, such as the movement of a tire on a gravel road. Vibration can be desirable: for example, the motion of a tuning fork, the Reed (music), reed in a woodwind instrument or harmonica, a mobile phone, or the cone of a loudspeaker. In many cases, however, vibration is undesirable, wasting energy and creating unwanted sound. For example, the vibrational motions of engines, electric motors, or any Machine, mechanical device in operation are typically unwanted. Such vibrations could be caused by Engine balance, imbalances in the rotating parts, uneven friction, or the meshing of gear teeth. Careful designs usually minimize unwanted vibrations. The studies of sound and vibration are closely related. Sound, or pressure waves, are ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Structure
In quantum chemistry, electronic structure is the state of motion of electrons in an electrostatic field created by stationary nuclei. The term encompasses both the wave functions of the electrons and the energies associated with them. Electronic structure is obtained by solving quantum mechanical equations for the aforementioned clamped-nuclei problem. Electronic structure problems arise from the Born–Oppenheimer approximation. Along with nuclear dynamics, the electronic structure problem is one of the two steps in studying the quantum mechanical motion of a molecular system. Except for a small number of simple problems such as hydrogen-like atoms, the solution of electronic structure problems require modern computers. Electronic structure problem is routinely solved with quantum chemistry computer programs. Electronic structure calculations rank among the most computationally intensive tasks in all scientific calculations. For this reason, quantum chemistry calculatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
