18,397 research outputs found
Investigation of in-plane nuclear field formation in single self-assembled quantum dots
We studied the formation mechanism of the in-plane nuclear field in single
self-assembled InAlAs/AlGaAs quantum dots.
The Hanle curves with an anomalously large width and hysteretic behavior at the
critical transverse magnetic field were observed in many single quantum dots
grown in the same QD sample. In order to explain the anomalies in the Hanle
curve indicating the formation of a large nuclear field perpendicular to the
photo-injected electron spin polarization, we propose a new model based on the
current phenomenological model for dynamic nuclear spin polarization. The model
includes the effects of the nuclear quadrupole interaction and the sign
inversion between in-plane and out-of-plane g-factors, and the model
calculations reproduce successfully the characteristics of the observed
anomalies in the Hanle curves.Comment: 7 pages, 6 figure
Lower Bound for Compactification Scale from Muon g - 2 in the Gauge-Higgs Unification
We discuss a muon anomalous magnetic moment in a five dimensional SU (3)
gauge- Higgs unification compactified on M^4 \times S^1 /Z_2 space-time
including Z_2 -odd bulk mass for a fermion. We calculate one-loop corrections
to the anomalous magnetic moment of muon and find a lower bound for the
compactification scale to be around 5 \sim 6 TeV by comparing nonzero
Kaluza-Klein mode contributions with the muon (g - 2) experiment at BNL.Comment: 42 pages, 22 ps files, We reanalyzed muon g-2 in the ten dimensional
representatio
Finite Anomalous Magnetic Moment in the Gauge-Higgs Unification
We show that the anomalous magnetic moment of fermion in the gauge-Higgs
unification is finite in any spacetime dimensions, which is a new predictive
physical observable similar to the Higgs mass.Comment: 12 pages, 2 eps files, final version to appear in PR
Temperature dependence of the spin and orbital magnetization density in around the spin-orbital compensation point
Non-resonant ferromagnetic x-ray diffraction has been used to separate the
spin and orbital contribution to the magnetization density of the proposed
zero-moment ferromagnet . The alignment of the
spin and orbital moments relative to the net magnetization shows a sign
reversal at 84K, the compensation temperature. Below this temperature the
orbital moment is larger than the spin moment, and vice versa above it. This
result implies that the compensation mechanism is driven by the different
temperature dependencies of the spin and orbital moments. Specific heat
data indicate that the system remains ferromagnetically ordered throughout
D^0-\bar D^0 Mixing in Gauge-Higgs Unification
We discuss flavor mixing and resulting Flavor Changing Neutral Current (FCNC)
in the SU(3) \otimes SU(3)_color gauge-Higgs unification. As the FCNC process
we calculate the rate of D^0-\bar D^0 mixing due to the exchange of non-zero
Kaluza-Klein gluons at the tree level. Flavor mixing is argued to be realized
by the fact that the bulk mass term and brane localized mass term is not
diagonalized simultaneously unless bulk masses are degenerate. It is shown that
automatic suppression mechanism is operative for the FCNC processes of light
quarks. We therefore obtain a lower bound on the compactification scale of
order \cal O(TeV) by comparing our prediction on the mass difference of neutral
D meson with the recent experimental data, which is much milder than what we
naively expect assuming only the decoupling of non-zero Kaluza-Klein gluons.Comment: 26 pages, 12 figures. arXiv admin note: text overlap with
arXiv:1005.245
Phenomenological Analysis of and Elastic Scattering Data in the Impact Parameter Space
We use an almost model-independent analytical parameterization for and
elastic scattering data to analyze the eikonal, profile, and
inelastic overlap functions in the impact parameter space. Error propagation in
the fit parameters allows estimations of uncertainty regions, improving the
geometrical description of the hadron-hadron interaction. Several predictions
are shown and, in particular, the prediction for inelastic overlap
function at TeV shows the saturation of the Froissart-Martin
bound at LHC energies.Comment: 15 pages, 16 figure
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