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Magnetization reversal through synchronization with a microwave
Based on the Landau-Lifshitz-Gilbert equation, it can be shown that a
circularly-polarized microwave can reverse the magnetization of a Stoner
particle through synchronization. In comparison with magnetization reversal
induced by a static magnetic field, it can be shown that when a proper
microwave frequency is used the minimal switching field is much smaller than
that of precessional magnetization reversal. A microwave needs only to overcome
the energy dissipation of a Stoner particle in order to reverse magnetization
unlike the conventional method with a static magnetic field where the switching
field must be of the order of magnetic anisotropy.Comment: 4 pages, 5 figure
The Relativistic Rotation
The classical rotation is not self-consistent in the framework of the special
theory of relativity. the Relativistic rotation is obtained, which takes the
relativistic effect into account. It is demonstrated that the angular frequency
of classical rotation is only valid in local approximation. The properties of
the relativistic rotation and the relativistic transverse Doppler shift are
discussed in this work
On the momentum-dependence of -nuclear potentials
The momentum dependent -nucleus optical potentials are obtained based
on the relativistic mean-field theory. By considering the quarks coordinates of
meson, we introduced a momentum-dependent "form factor" to modify the
coupling vertexes. The parameters in the form factors are determined by fitting
the experimental -nucleus scattering data. It is found that the real
part of the optical potentials decrease with increasing momenta, however
the imaginary potentials increase at first with increasing momenta up to
MeV and then decrease. By comparing the calculated mean
free paths with those from / scattering data, we suggested that the
real potential depth is MeV, and the imaginary potential parameter
is MeV.Comment: 9 pages, 4 figure
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