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The current induced local spin polarization due to weak Rashba spin-orbit coupling in narrow strip is studied. In the presence of longitudinal charge current, local spin polarizations appear in the sample. The spin polarization perpendicular to the plane has opposite sign near the two edges. The in-plane spin polarization in the direction perpendicular to the sample edges also appears, but does not change sign across the sample. From our scaling analysis based on increasing the strip width, the out-of-plane spin polarization is important mainly in a system of mesoscopic size, and thus appears not to be associated with the spin-Hall effect in bulk samples. [ABSTRACT FROM AUTHOR]

In this paper we use the so-called static fluctuation approximation (SFA) to calculate the thermodynamic properties of spin-polarized atomic hydrogen. This approximation is based on the replacement of the square of the local-field operator with its mean value. A closed set of nonlinear integral equations is derived for neutral many-bosonic systems. This set is solved numerically by an iteration method for two triplet-state potentials: a Morse- and Silvera-type potentials. It is found that the mean internal energy per unit volume, the pressure, the entropy per unit volume, and the specific heat per unit volume increase with temperature and decrease with spin polarization in the low-temperature region (<8mK); whereas the condensate fraction increases with an applied magnetic field. It is also found that these quantities are nearly independent of spin polarization for high temperatures (>0.1K), and that they are independent of the number density up to 10-3Å-3 in the low-temperature region. [ABSTRACT FROM AUTHOR]

We present in this work a theory of magnetization (M) in diluted magnetic semiconductors and express it as sum of contributions due to magnetic impurities (Mi) and band effects which include lattice diamagnetism (Mdia) and spin density due to carriers (Mc). In addition to the contribution of isolated magnetic ions (Ms), Mi includes the contributions of three types of small clusters: pairs (Mp), open triplets (Mot) and closed triplets (Mct). The contributions due to impurity spin interactions were calculated using modified Heisenberg's Hamiltonian as applicable to these clusters within the nearest neighbor interaction approximation. The band effects include contributions due to lattice diamagnetism and spin density due to carriers. The lattice diamagnetism χdia was calculated using a two band model for the host system and a modified one for the alloy systems. χdia for the host system compare well with the available experimental results. Mc was calculated using a formula derived from first principles for an interacting electronic system. This is modified to calculate Mc in the p-type Pb1-xMnxTe and Pb1-xEuxTe. Although the band effects are found to be small in the context of analyzing magnetization, they are intrinsically important in the sense that these quantities shed light on the nature of mechanisms contributing to lattice diamagnetism and the carrier spin densities in these systems. [ABSTRACT FROM AUTHOR]

Phase synchronization of a chaotic oscillator that is driven by two chaotic signals is investigated. The anti-biased PS in the presence of biased coupling is found, i.e., the response oscillator can be phase synchronized by the drive with a weaker coupling rather than the stronger driver. The mechanism for this behavior is explored. In the non-PS region, alternating phase-locking is observed. [ABSTRACT FROM AUTHOR]

We study the magnetization and the magnetic phases of II-VI-based n-doped nonmagnetic- semiconductor (NMS) / narrow to wide dilute-magnetic-semiconductor (DMS) / n-doped NMS quantum wells under in-plane magnetic field. The parallel magnetic field is used as a tool, in order to achieve non-step-like density of states in these -appropriate for conduction-band spintronics- structures. [ABSTRACT FROM AUTHOR]

In this paper, we study the electron transport properties in the double non-collinear δ-magnetic barriers within 2-dimensional electron gas. We find that the transmission of spin current depends on the relative orientation of each magnetic barrier. In addition to the well-known unpolarized configurations in an antiparallel magnetic barrier structure, we also find that there exists infinite unpolarized structures due to the time-reversal symmetry. These structures will be important in the designs of spin valve. [ABSTRACT FROM AUTHOR]

Transitions between spin polarized and spin singlet incompressible ground state of quantum Hall systems at filling factor ⅔ are studied by means of exact diagonalization with eight electrons. We observe a stable exactly half-polarized state becoming the absolute ground state around the transition point. This might be a candidate for the anomaly observed during the transition in optical experiments. The state reacts strongly to magnetic inhomogeneities but it prefers stripe-like spin structures to formation of domains. [ABSTRACT FROM AUTHOR]

The strong scattering limit of the magnetic field dependence of the local phonon-assisted nuclear spin relaxation rate, (NSRR), in two dimensional electron systems, (2DES) with magnetic impurities is calculated. It is shown that the NSRR can be tuned resonantly, by external magnetic field, due to the possibility of matching the electron Zeeman splitting with the energy spacing between the localized vibrational modes created by the lattice distortion around the impurity. This new resonance phenomenon could be used to manipulate, with high precision, the relaxation and decoherence times of nuclear spin based quantum information processing devices. [ABSTRACT FROM AUTHOR]

Electrical transport measurements are reported on 2-DEG in a CdMnTe quantum well structure. At low magnetic fields the Shubnikov-de Haas oscillations show a beating pattern with nodes which are a direct consequence of the large Pauli paramagnetism. The effective electron Zeeman splitting (EZ) has been tuned via the s-d exchange interaction in order to probe the quantum Hall effect under conditions of vanishing Zeeman energy. We have observed that reducing EZ to zero does not necessary imply a closing of the spin gap. [ABSTRACT FROM AUTHOR]

We present spin-resolved electronic properties of digitally Mn-doped diluted magnetic semiconductor (DMS) quantum wells (QWs) with an emphasis on the control of spontaneous magnetization and spin carrier distributions in terms of QW structure parameters and doping profiles of the magnetic ions. A combined Schrödinger and Poisson equation is solved numerically to obtain self-consistent subband wavefunctions and energies of the holes in the DMS QWs. Self-consistent spin-resolved subband structure shows that (i) the spatial distributions of the majority and minority spin carriers are separated in the DMS QW below the Curie temperature and (ii) the spontaneous magnetization of the Mn-doped magnetic nanostructure depends sensitively on doping profiles of the magnetic ion and the strength of exchange couplings. [ABSTRACT FROM AUTHOR]

The symmetry properties and the general overview of the superconductivity theory in the itinerant ferromagnets and in materials without space parity are presented. The basic notions of unconventional superconductivity are introduced in broad context of multiband superconductivity which is an inherent property of ferromagnetic metals or metals without centre of inversion. [ABSTRACT FROM AUTHOR]

We report the observations, using magnetic susceptibility and specific heat measurements, of the coexistence of superconductivity and magnetic ordering at low temperatures in the Cu-doping double perovskites Sr[sub 2]ARu[sub 1-χ]Cu[sub χ]O[sub 6], with A = Y or Ho, and χ < 0.2. The observed striking features can be understood in terms of a plausible theoretical model based on the double exchange mechanism, which occurs indirectly via Ru[sup 5+] spin coupling to itinerant electrons hopping from one Ru site to another. [ABSTRACT FROM AUTHOR]

The density matrix renormalization group theory is reviewed as a numerical variational method. The variational state, expressed as a product of local tensors, is improved through locally tuning each tensor. The first section is a tutorial with simplified discussions. Details are discussed in the subsequent sections. The review concludes with some recent developments and future directions. [ABSTRACT FROM AUTHOR]