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Layer expansion of layered silicates in solid polymer matrices by compression
Perturbational approach to the quantum capacity of additive Gaussian quantum channel
For a quantum channel with additive Gaussian quantum noise, at the large
input energy side, we prove that the one shot capacity is achieved by the
thermal noise state for all Gaussian state inputs, it is also true for
non-Gaussian input in the sense of first order perturbation. For a general case
of copies input, we show that up to first order perturbation, any
non-Gaussian perturbation to the product thermal state input has a less quantum
information transmission rate when the input energy tend to infinitive.Comment: 5 page
Magnetically-induced electric polarization in an organo-metallic magnet
The coupling between magnetic order and ferroelectricity has been under
intense investigation in a wide range of transition-metal oxides. The strongest
coupling is obtained in so-called magnetically-induced multiferroics where
ferroelectricity arises directly from magnetic order that breaks inversion
symmetry. However, it has been difficult to find non-oxide based materials in
which these effects occur. Here we present a study of copper dimethyl sulfoxide
dichloride (CDC), an organo-metallic quantum magnet containing Cu
spins, in which electric polarization arises from non-collinear magnetic order.
We show that the electric polarization can be switched in a stunning hysteretic
fashion. Because the magnetic order in CDC is mediated by large organic
molecules, our study shows that magnetoelectric interactions can exist in this
important class of materials, opening the road to designing magnetoelectrics
and multiferroics using large molecules as building blocks. Further, we
demonstrate that CDC undergoes a magnetoelectric quantum phase transition where
both ferroelectric and magnetic order emerge simultaneously as a function of
magnetic field at very low temperatures
Chiral geometry and rotational structure for Cs in the projected shell model
The projected shell model with configuration mixing for nuclear chirality is
developed and applied to the observed rotational bands in the chiral nucleus
Cs. For the chiral bands, the energy spectra and electromagnetic
transition probabilities are well reproduced. The chiral geometry illustrated
in the and the is confirmed to be stable against the
configuration mixing. The other rotational bands are also described in the same
framework
A Comparative Study on the Use of Classification Algorithms in Financial Forecasting
Financial forecasting is a vital area in computational finance, where several studies have taken place over the years. One way of viewing financial forecasting is as a classification problem, where the goal is to find a model that represents the predictive relationships between predictor attribute values and class attribute values. In this paper we present a comparative study between two bio-inspired classification algorithms, a genetic programming algorithm especially designed for financial forecasting, and an ant colony optimization one, which is designed for classification problems. In addition, we compare the above algorithms with two other state-of-the-art classification algorithms, namely C4.5 and RIPPER. Results show that the ant colony optimization classification algorithm is very successful, significantly outperforming all other algorithms in the given classification problems, which provides insights for improving the design of specific financial forecasting algorithms
Current-voltage characteristics in donor-acceptor systems: Implications of a spatially varying electric field
We have studied the transport properties of a molecular device composed of
donor and acceptor moieties between two electrodes on either side. The device
is considered to be one-dimensional with different on-site energies and the
non-equilibrium properties are calculated using Landauer's formalism. The
current-voltage characteristics is found to be asymmetric with a sharp Negative
Differential Resistance at a critical bias on one side and very small current
on the other side. The NDR arises primarily due to the bias driven electronic
structure change from one kind of insulating phase to another through a highly
delocalized conducting phase. Our model can be considered to be the simplest to
explain the experimental current-voltage characteristics observed in many
molecular devices.Comment: 5 pages, 4 figures (accepted for publication in Physical Review B
2D continuous spectrum of shear Alfven waves in the presence of a magnetic island
The radial structure of the continuous spectrum of shear Alfven modes is
calculated in the presence of a magnetic island in tokamak plasmas. Modes with
the same helicity of the magnetic island are considered in a slab model
approximation. In this framework, with an appropriate rotation of the
coordinates the problem reduces to 2 dimensions. Geometrical effects due to the
shape of the flux surface's cross section are retained to all orders. On the
other hand, we keep only curvature effects responsible of the beta induced gap
in the low-frequency part of the continuous spectrum. New continuum
accumulation points are found at the O-point of the magnetic island. The
beta-induced Alfven Eigenmodes (BAE) continuum accumulation point is found to
be positioned at the separatrix flux surface. The most remarkable result is the
nonlinear modification of the BAE continuum accumulation point frequency
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