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The exchange bias effect, discovered more than fifty years ago, is a fundamental interfacial property, which occurs between ferromagnetic and antiferromagnetic materials. After intensive experimental and theoretical research over the last ten years, a much clearer picture has emerged about this effect, which is of immense technical importance for magneto-electronic device applications. In this review we start with the discussion of numerical and analytical results of those models which are based on the assumption of coherent rotation of the magnetization. The behavior of the ferromagnetic and antiferromagnetic spins during the magnetization reversal, as well as the dependence of the critical fields on characteristic parameters such as exchange stiffness, magnetic anisotropy, interface disorder etc. are analyzed in detail and the most important models for exchange bias are reviewed. Finally recent experiments in the light of the presented models are discussed. [ABSTRACT FROM AUTHOR]

We review the recent progress for spin injection into semiconductors. After discussing the physical background on the basis of the optical selection rules we describe spin injection via magnetic semiconductors and ferromagnetic metal contacts. The concepts for optical detection of spin injection and the problem of spin relaxation in the semiconductor are analyzed before we finally address spin - optoelectronic devices, namely the spin light-emitting diode (spin-LED) and the spin vertical-cavity surfaceemitting laser (spin-VCSEL). [ABSTRACT FROM AUTHOR]

We review the present status of the experimental and theoretical research on the proximity effect in heterostructures composed of superconducting (S) and ferromagnetic (F) thin films. First, we discuss traditional effects originating from the oscillatory behavior of the superconducting pair wave function in the F-layer. Then, we concentrate on recent theoretical predictions for S/F layer systems. These are a) generation of odd triplet superconductivity in the F-layer and b) ferromagnetism induced in the S-layer below the superconducting transition temperature Tc (inverse proximity effect). The second part of the review is devoted to discussion of experiments relevant to the theoretical predictions. In particular, we present results of measurements of the critical temperature Tc as a function of the thickness of F-layers and we review experiments indicating the existence of the odd triplet superconductivity, cryptoferromagnetism and inverse proximity effect. [ABSTRACT FROM AUTHOR]

Spintronics devices employ a wide range of magnetic multilayer structures. In this chapter the coupling between the magnetic layers through non-magnetic spacers will be reviewed. It starts with phenomenology of interlayer magnetic coupling. This is followed by experimental techniques and a detailed interpretation of measurements. The main emphases will be given to the static and rf measurement techniques. Theory of magnetic coupling covers the basic ideas of interlayer exchange coupling and dipolar coupling. The additional contributions caused by imperfections in realistic samples are discussed in sessions on orange peel coupling, pinhole coupling, and biquadratic exchange coupling. Experimental results and their interpretation were carried out to emphasize the richness of magnetic interactions in a wide range of systems. A particular attention was given to the Fe/Ag,Au/Fe, Co/Cu/Co and Fe/Cr,Mn,Pd/Fe structures allowing one to demonstrate the importance of interfaces on magnetic coupling in multilayer systems. Finally, it is shown that the time retarded response of interlayer exchange interaction leads to an entirely new coupling which is based on spin pumping and spin sink concepts. This contribution arises only during spin dynamics and compared to the static interlayer exchange coupling is long ranged allowing one in principle move information by means of a spin current via a mechanism that does not directly involve a net transport of electron charge [ABSTRACT FROM AUTHOR]

In magnetoelectronic devices large opportunities are opened by the spin dependent tunneling resistance, where a strong dependence of the tunneling current on the relative orientation of the magnetization of the electrodes is found. Within a short time, the amplitude of the resistance change of the junctions increased dramatically. We will cover Al-O and MgO based junctions and present highly spin-polarized electrode materials such as Heusler alloys. Furthermore, we will give a short overview on applications such as read heads in hard disk drives, storage cells in MRAMs, field programmable logic circuits and biochips. Finally, we will discuss the currently growing field of current induced magnetization switching. [ABSTRACT FROM AUTHOR]

The chapter provides a detailed introduction to magnetic anisotropy of ferromagnetic ultrathin films and its analysis by ferromagnetic resonance on a tutorial level. While the microscopic origins of the magnetic anisotropy as well as recent developments in its theoretical description are shortly discussed, emphasis is put on a phenomenological description using the free energy of the system together with its symmetries. The formalism is used to describe ferromagnetic resonance experiments which present an extremely sensitive method to experimentally investigate magnetic anisotropy in thin film heterostructures. Expressions for the free energy and the resonance equations are derived for the most widely used crystal symmetries such as cubic, tetragonal and hexagonal. The general equations are illustrated by giving selected examples of current research on thin metallic films on different kinds of substrates (MgO, GaAs and Cu). [ABSTRACT FROM AUTHOR]

The growth and characterization of magnetic materials has progressed substantially during the last decades. In this chapter we give a brief overview of this vastly growing field of research. We highlight some of the relevant growth techniques for different materials classes but we do not intend to be complete with respect to technical details or materials systems. We also outline some of the concepts and theories of the growth of modern magnetic materials, emphasizing the role of first principles calculations in providing microscopic understanding of the growth mechanisms. We discuss the growth of metallic and oxide single crystal films, multilayers and superlattices and the influence of thickness, strain, crystallinity, structure and morphology on the resulting magnetic properties. [ABSTRACT FROM AUTHOR]

Theoretically, light muonic atoms have two main special features as compared with the ordinary electronic hydrogenlike atoms, both of which are connected with the fact that the muon is about 200 times heavier than the electron1. First, the role of the radiative corrections generated by the closed electron loops is greatly enhanced, and second, the leading proton size contribution becomes the second largest individual contribution to the energy shifts after the polarization correction. [ABSTRACT FROM AUTHOR]

Theoretical results described above find applications in numerous high precision experiments with hydrogen, deuterium, helium, muonium, muonic hydrogen, etc. Detailed discussion of all experimental results in comparison with theory would require as much space as the purely theoretical discussion above. We will consider below only some applications of the theory, intended to serve as illustrations, their choice being necessarily somewhat subjective and incomplete (see also detailed discussion of phenomenology in the recent reviews [1, 2]). [ABSTRACT FROM AUTHOR]

The very presence of the recoil factor m/M emphasizes that the external field approach is inadequate for calculation of recoil corrections and, in principle, one needs the complete machinery of the two-particle equation in this case. However, many results may be understood without a cumbersome formalism. [ABSTRACT FROM AUTHOR]

The hyperfine splitting in the ground state of hydrogen is one of the most precisely measured quantities in modern physics [1, 2] (see for more details Subsect. 12.2.1 below), and to describe it theoretically we need to consider additional contributions to HFS connected with the bound state nature of the proton. [ABSTRACT FROM AUTHOR]

Relativistic and radiative corrections depend on the electron and muon masses only via the explicit mass factors in the electron and muon magnetic moments, and via the reduced mass factor in the Schrödinger wave function. All such corrections may be calculated in the framework of the external field approximation. [ABSTRACT FROM AUTHOR]

The theory of the atomic energy levels developed in the previous chapter is incomplete, since we systematically ignored the nuclear spin which leads to an additional splitting of the energy levels. This effect will be the subject of our discussion below. [ABSTRACT FROM AUTHOR]

The one-electron atom is a composite nonrelativistic system loosely bound by electromagnetic forces. The characteristic size of the atom is of the order of the Bohr radius 1/(mZα), and this scale is too large for effects of other interactions (weak and strong, to say nothing about gravitational) to play a significant role. [ABSTRACT FROM AUTHOR]

In the standard nomenclature the name radiative-recoil is reserved for the recoil corrections to pure radiative effects, i.e., for corrections of the form αm(Zα)n(m/M)k. [ABSTRACT FROM AUTHOR]

We will first discuss corrections to the basic Dirac energy levels which arise in the external field approximation. These are leading relativistic corrections with exact mass dependence and radiative corrections. [ABSTRACT FROM AUTHOR]

Leading relativistic corrections of order (Zα)4 and their mass dependence were discussed above in Sect. 3.1 in the framework of the Breit equation and the effective Dirac equation in the external field in Fig. 1.6. The exact mass dependence of these corrections could be easily calculated because all these corrections are induced by the one-photon exchange. [ABSTRACT FROM AUTHOR]

The zero-order effective Dirac equation with a Coulomb source provides only an approximate description of loosely bound states in QED, but the spectrum of this Dirac equation may serve as a good starting point for obtaining more precise results. [ABSTRACT FROM AUTHOR]

In the first approximation, energy levels of one-electron atoms (see Fig. 1.1) are described by the solutions of the Schrödinger equation for an electron in the field of an infinitely heavy Coulomb center with charge Z in terms of the proton charge1 [ABSTRACT FROM AUTHOR]

As has become clear in the previous Chapter, the most challenging domain for a dynamical theory of escape processes, i.e. a description in real-time, is the low temperature range. There, quantum mechanical non-locality renders any standard semiclassical approach to fail. [ABSTRACT FROM AUTHOR]