239,859 research outputs found
Non-Volatile Magnonic Logic Circuits Engineering
We propose a concept of magnetic logic circuits engineering, which takes an
advantage of magnetization as a computational state variable and exploits spin
waves for information transmission. The circuits consist of magneto-electric
cells connected via spin wave buses. We present the result of numerical
modeling showing the magneto-electric cell switching as a function of the
amplitude as well as the phase of the spin wave. The phase-dependent switching
makes it possible to engineer logic gates by exploiting spin wave buses as
passive logic elements providing a certain phase-shift to the propagating spin
waves. We present a library of logic gates consisting of magneto-electric cells
and spin wave buses providing 0 or p phase shifts. The utilization of phases in
addition to amplitudes is a powerful tool which let us construct logic circuits
with a fewer number of elements than required for CMOS technology. As an
example, we present the design of the magnonic Full Adder Circuit comprising
only 5 magneto-electric cells. The proposed concept may provide a route to more
functional wave-based logic circuitry with capabilities far beyond the limits
of the traditional transistor-based approach
Rotation in an exact hydro model
We study an exact and extended solution of the fluid dynamical model of heavy
ion reactions, and estimate the rate of slowing down of the rotation due to the
longitudinal and transverse expansion of the system. The initial state
parameters of the model are set on the basis of a realistic 3+1D fluid
dynamical calculation at TeV energies, where the rotation is enhanced by the
build up of the Kelvin Helmholtz Instability in the flow
Angular-dependent Magnetoresistance Oscillations in NaCoO Single Crystal
We report measurements of the c-axis angular-dependent magnetoresistance
(AMR) for a NaCoO single crystal, with a magnetic field of 10 T
rotating within Co-O planes. Below the metal-insulator transition temperature
induced by the charge ordering, the oscillation of the AMR is dominated by a
two-fold rotational symmetry. The amplitudes of the oscillation corresponding
to the four- and six-fold rotational symmetries are distinctive in low
temperatures, but they merge into the background simultaneously at about 25 K.
The six-fold oscillation originates naturally from the lattice symmetry. The
observation of the four-fold rotational symmetry is consistent with the picture
proposed by Choy, et al., that the Co lattice in the charge ordered state will
split into two orthorhombic sublattice with one occupied by Co ions and
the other by Co ions. We have also measured the c-axis AMR for
NaCoO and NaCoO single crystals, and found no
evidence for the existence of two- and four-fold symmetries.Comment: 4 pages, 6 figures. Submitted to PR
Local Density Approximation Description of Electronic Properties of Wurtzite Cadmium Sulfide (w-CdS)
We present calculated, electronic and related properties of wurtzite cadmium
sulfide (w-CdS). Our ab-initio, non-relativistic calculations employed a local
density functional approximation (LDA) potential and the linear combination of
atomic orbitals (LCAO). Following the Bagayoko, Zhao, and Williams (BZW)
method, we solved self-consistently both the Kohn-Sham equation and the
equation giving the ground state density in terms of the wave functions of the
occupied states. Our calculated, direct band gap of 2.47 eV, at the point, is
in excellent agreement with experiment. So are the calculated density of states
and the electron effective mass. In particular, our results reproduce the peaks
in the conduction band density of states, within the experimental
uncertainties.Comment: 22 Pages 4 Figure
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