Spin transport properties at finite electric and magnetic fields are studied by using the generalized semiclassical Boltzmann equation. It is found that the spin diffusion equation for non-equilibrium spin density and spin currents involves a number of length scales that explicitly depend on the electric and magnetic fields. The set of macroscopic equations can be used to address a broad range of the spin transport problems in magnetic multilayers as well as in semiconductor heterostructure. A specific example of spin injection into semiconductors at arbitrary electric and magnetic fields is illustrated

We propose an improved method of the equation of motion approach to study the Kondo problem in spin-dependent nonequilibrium conditions. We find that the previously introduced additional renormalization for nonequilibrium Kondo effects is not required when we use a proper decoupling scheme. Our improved formulation is then applied to address the spin-split Kondo peaks when a spin current injects into a Kondo system. J FMMagnetic impurity STM J J

We predict that the flow of unpolarized current in electron-doped GaAs and InP at room temperature is unstable at high electric fields to the dynamic formation of spin-polarized current pulses. Spin-polarized current is spontaneously generated because the conductivity of a spin-polarized electron gas differs from that of an unpolarized electron gas, even in the absence of spin-orbit interaction. Magnetic fields are not required for the generation of these spin-polarized current pulses, although they can help align the polarization of sequential pulses along the same axis.

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Oral sodium nitrite administration is well tolerated in diabetes patients.

Using the Slonczewski model with a ␦-type potential barrier, we study spin-dependent tunneling conductances in a tunnel junction composed of two ferromagnetic layers ͑FM's͒ separated by an insulating barrier ͑I͒.In the high barrier case, the expression for the tunneling magnetoresistance is found to have the same form as that proposed by Julliere, but the electron-spin polarizations in both models have different definitions. We suggest that the spin dependence of the transmission coefficient should be taken into account in a FM/I/FM tunnel junction, and so the present formula can better describe its tunneling magnetoresistance.

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We experimentally demonstrate C-band 2 × 56 Gb/s pulse-amplitude modulation (PAM)-4 signal transmission over 100 km standard single-mode fiber (SSMF) using 18 GHz direct-modulated lasers (DMLs) and direct detection, without inline optical amplifier. A delay interferometer (DI) at the transmitter side is used to extend the transmission reach from 40 to 100 km. A digital Volterra filter at the receiver side is used to mitigate the nonlinear distortions. We obtain an average bit error ratio (BER) of 1.5 × 10(-3) for 2 × 56 Gb/s PAM-4 signal after 100 km SSMF transmission at the optimal input power, which is below the 7% forward error correction (FEC) threshold (3.8 × 10(-3)).