638 research outputs found
The Ebers-Moll model for magnetic bipolar transistors
The equivalent electrical circuit of the Ebers-Moll type is introduced for
magnetic bipolar transistors. In addition to conventional diodes and current
sources, the new circuit comprises two novel elements due to spin-charge
coupling. A classification scheme of the operating modes of magnetic bipolar
transistors in the low bias regime is presented.Comment: 4 pages, 2 figure
Spin switch and spin amplifier: magnetic bipolar transistor in the saturation regime
It is shown that magnetic bipolar transistors (MBT) can amplify currents even
in the saturation regime, in which both the emitter-base and collector-base
junctions are forward biased. The collector current and the current gain can
change sign as they depend on the relative orientation of the equilibrium spin
in the base and on the nonequilibrium spin in the emitter and collector. The
predicted phenomena should be useful for electrical detection of nonequilibrium
spins in semiconductors, as well as for magnetic control of current
amplification and for current switching.Comment: 5 pages, 4 figures; paper to a presentation at XXXIII International
School on the Physics of Semiconductor Compounds Jaszowiec 200
Computation of the Nonlinear Magnetic Response of a Three Dimensional Anisotropic Superconductor
Many problems in computational magnetics involve computation of fields which
decay within a skin depth , much smaller than the sample size . We
discuss here a novel perturbation method which exploits the smallness of
and the asymptotic behavior of the solution in the
exterior and interior of a sample. To illustrate this procedure we consider the
computation of the magnetic dipole and quadrupole moments of an anisotropic,
unconventional, three dimensional superconductor. The method significantly
reduces the required numerical work and can be implemented in different
numerical algorithms.Comment: Three pages. To appear in Journal of Applied Physics (MMM-Intermag
issue
A proposal for a spin-polarized solar battery
A solar cell illuminated by circularly-polarized light generates charge and
spin currents. We show that the spin polarization of the current significantly
exceeds the spin polarization of the carrier density for the majority carriers.
Based on this principle we propose a semiconductor spin-polarized solar battery
and substantiate our proposal using analytical arguments and numerical
modeling.Comment: 4 pages, 3 figure
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