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Magnetic NPs containing 3D transition metal oxides or relative mixtures are one of the most studied nanomaterials in view of their prospective, ubiquitous applications in quite different areas, the most important being biomedicine, sensor technology, and magnetic recording [1]. According to their usage, magnetic NPs are often either embedded in a diamagnetic solid [2] or dispersed in a fluid; in some cases they are surrounded by an outer shell of a diamagnetic material. [ABSTRACT FROM AUTHOR]

We review the effects of electron–electron interactions on the ground-state spin and the transport properties of ultra-small chaotic metallic grains. Our studies are based on an effective Hamiltonian that combines a superconducting BCS-like term and a ferromagnetic Stoner-like term. Such terms originate in pairing and spin exchange correlations, respectively. This description is valid in the limit of a large dimensionless Thouless conductance. We present the ground-state phase diagram in the fluctuation-dominated regime where the single-particle mean level spacing is comparable to the bulk BCS pairing gap. This phase diagram contains a regime in which pairing and spin exchange correlations coexist in the ground-state wave function. We discuss the calculation of the tunneling conductance for an almost-isolated grain in the Coulomb-blockade regime, and present measurable signatures of the competition between superconductivity and ferromagnetism in the mesoscopic fluctuations of the conductance. [ABSTRACT FROM AUTHOR]

A new interpretation of the Higgs field on the basis of a non-orthodox approach to the Weinberg-Salam (WS) model is suggested. It is argued that the masses of vector mesons can be generated without the use of the Higgs potential. [ABSTRACT FROM AUTHOR]

Like harmony in music; there is a dark inscrutable workmanship that reconciles discordant elements, makes them cling together in one society. The products of the glass maker are often aesthetically pleasing, but it would be unfair to claim that glass is intrinsically more attractive than any other type of material. Rather, by its presence in the family of materials, glass extends the range of useful properties and artistic qualities. As has transpired only recently, glass also extends the range of atomic structures in condensed matter, through its unique lack of order. Indeed, it is this atomic-level attribute, rather than the traditional ones of transparency and brittleness, which is now acknowledged as the defining characteristic of this type of material. Oxide glasses such as the common silicate varieties have been in use for at least 4000 years. Glass beads, dating from about 2500 BC, have been found in Egypt and other parts of the Near East, although exploitation of the plasticity of hot glass is more recent. These oxide materials so dominated the scene that the existence of the glassy state was believed to be intimately connected with the presence of covalent bonds. Glass has long been known to be a supercooled liquid, and covalent bonding was regarded as a prerequisite if crystallization was to be avoided. These attitudes underwent radical revision in the 1960s. With the production of metallic examples, it was suddenly realized that a glass need not be transparent, brittle, or insulating. [ABSTRACT FROM AUTHOR]

There was no ‘One, two, three, and away’, but they began running when they liked and left off when they liked, so that it was not easy to know when the race was over. Of all technological accomplishments, none so epitomizes human skill and ingenuity as the harnessing of electricity. Because so much of modern existence is based on it, electrical energy is inevitably taken for granted. Only occasional power failures are capable of reminding us just how dependent we are on this invisible commodity. The practical use of electricity is a surprisingly recent development. It is hard to believe that many of the scientists who precipitated this revolution, made their discoveries as recently as in the nineteenth century, and frequently wrote up their laboratory notes by candle-light. The great advances in atomic physics, early in the twentieth century, paved the way for a second revolution: solid state electronics. Its impact on society has been enormous, giving rise to new industries, new professions, new communication techniques and new organizations. Both revolutions depended, to an exceptional degree, on progress in fundamental science. The people responsible for this breathtaking series of innovations were primarily concerned with abstract ideas, but their efforts have given society radio, television, the telephone, the computer, new forms of heating, lighting, power and transport, and a host of other developments. Many electrical phenomena are transient in nature, whereas magnetism has the advantage of relative permanence. [ABSTRACT FROM AUTHOR]

The article discusses the structured materials of smart perovskites. Perovskites is probably the most important structural type of materials, it have important applications in ferroelectricity, piezoelectricity, ferromagnetism, magnetoresisitance, superconductivity, ionic conductivity, and dieelectricity.

The article discusses the application of shape-memory alloys to a magnetically ferromagnetic materials. It describes the crystallography and magnetism of nikel-magnesium-galuim in order to explain the very large strains produced by field-induced twin-boundary motion in martensite.

The article discusses the magnetostrictive transducers that can convert energy between the magnetic and the elastic states. Magnetostriction is an inherent property of ferromagnetic materials. With more established technologies, newer magnetostrictive materials provide unique combination of high forces, energy densities, operating bandwidths and coupling coefficients. The development of magnetostriction is due to the coupling between magnetic moment orientation and magnetomechanical coupling.

The article discusses the evolution of magnetism leading to the development of telecommunication devices and magnetic storage for computers. Magnetism is a coupling of unpaired electron spins. Coupled alignment of electron spins lead to a ferromagnet or substantial magnetic moment while the incomplete cancellation of spins lead to a ferrimagnet or net magnetic moment. Uncoupled spins lead to a paramagnetic behavior. Applications of organic magnets include electronic and photonic devices.

The article presents information about Q-meters. The Q of an inductor is a function of the frequency of measurement. The loss mechanisms for inductor loss are functions of frequency. Skin effect causes increased resistance with increasing frequency, and hence increased resistance losses. Radiation also increases with increasing frequency because the physical dimensions of the inductor become a more significant part of a wavelength. When ferromagnetic material is used in the core of an inductor, the frequency dependence of the inductor's Q can become quite complex. Shielded enclosures are often used to reduce the amount of radiation from an inductor, and this adds even more complexity to the Q factor calculation.

This article presents information on magnetic sensors. Generally, magnetic sensors are based on sensing the properties of magnetic materials, which can be done in many ways. For example, magnetization, which is the magnetic moment per volume of materials, is used in many measurement systems by sensing force, induction, field methods, and superconductivity. In instrumentation applications, the magnetic field may be varying in time with some frequency, and the conductor may be moving at the same time.

This article focuses on Barkhausen Effect or Barkhausen Noise. The change of the magnetic state of a ferro- or ferrimagnetic body under the effect of a slowly changing externally applied magnetic field is a complex process, involving reversible and irreversible changes of the magnetization. Due to irreversible magnetization processes, any change of the magnetic state is accompanied by losses, manifested in the presence of the magnetic hysteresis. This process and the corresponding noise is named after its discoverer, H. Barkhausen as Barkhausen jumps and Barkhausen noise. In the demagnetized state the distribution of the magnetization inside of the magnetic body is nonuniform. The magnetic structure consists of domains, small regions of different magnetization direction.

This article describes the magnetization reversal processes and the time-dependent reversal phenomena that occur when data are stored in magnetic recording media. These reversal processes determine the response of the medium to the applied magnetic field during the writing of data and the stability of written data patterns over the lifetime of the medium. Information is written onto hard-disk magnetic recording media when a magnetic write head passes near the surface of the recording medium. The head is magnetized by a varying current whose polarity changes according to a digitized stream of data.

This article presents information on electromagnetic (EM) shielding. EM shielding represents a way to limit the emission levels of EM sources or to protect people or electrical and electronics apparatus and systems against possible effects due to external EM fields. One of the most challenging research topics is the analysis and the design of real shielding structures. In particular, low-frequency magnetic fields are shielded with difficulty and often by means of nonlinear and expensive ferromagnetic materials, requiring computer-aided design of shielding structures.

The establishment of the Standard Model marked the attainment of another stage in the attempt to give a unified description of the forces of nature. The program was initiated at the beginning of the nineteenth century by Oersted and Faraday, the “natural philosophers,” who, influenced by Naturphilosophie, gave credibility to the quest and provided the first experimental indication that the program had validity. Thereafter, Maxwell constructed a model for a unified theory of electricity and magnetism, providing a mathematical formulation that was able to explain much of the observed phenomena and to make predictions of new ones. With Einstein the vision became all-encompassing. In addition, Einstein advocated a radical form of theory reductionism. For him the supreme test of the physicist was “to arrive at those universal elementary laws from which the cosmos can be built up by pure deduction.” A commitment to reductionism and a desire for unification animated the quest for the understanding of the subnuclear domain – and success in obtaining an effective representation was achieved by those committed to that vision. The formulation of the Standard Model is one of the great achievements of the human intellect – one that rivals the genesis of quantum mechanics. It will be remembered – together with general relativity, quantum mechanics, and the unravelling of the genetic code – as one of the outstanding intellectual advances of the twentieth century. But much more so than general relativity and quantum mechanics, it is the product of a communal effort. [ABSTRACT FROM AUTHOR]

This panel was intended to function as a discussion, but instead it emerged as a series of short presentations by the participants Robert Brout, Tian Yu Cao, and Peter Higgs, with an introductory discussion by the chair. The present chapter consists of a revised and edited version of those reports and also includes a later submission by Yoichiro Nambu, who was scheduled to be on the panel originally but was unable to attend. Introduction The two sectors of the current Standard Model of particle physics, the strong color and the electroweak sectors, are distinct and are tied together only by ontology. Together, they describe the interactions, other than gravitation, of the three generations of quarks and leptons. The dream of representing the strong and weak “nuclear” interactions (as they were known before the acceptance of the quarks) as quantum field theories (QFT) goes back to the 1930s. The first such QFT, other than quantum electrodynamics, was Enrico Fermi's weak-interaction theory of 1934. This theory was almost immediately extended by Werner Heisenberg in 1935 to include the strong interactions (thus making it the first unified QFT) whose exchanged “quanta” were those of the electron-neutrino “Fermi-field.” In 1935, Hideki Yukawa invented “U-quanta,” now called pions, to represent the field of strong interactions, adjusting their mass to fit the range of nuclear forces. This was again a unified QFT, as the U-quanta were also intended to serve as intermediate bosons of the weak interaction. [ABSTRACT FROM AUTHOR]