4,025 research outputs found
Mapping correlated Gaussian patterns in a perceptron
The authors study the performance of a single-layer perceptron in realising a binary mapping of Gaussian input patterns. By introducing non-trivial correlations among the patterns, they generate a family of mappings including easier ones where similar inputs are mapped into the same output, and more difficult ones where similar inputs are mapped into different classes. The difficulty of the problem is gauged by the storage capacity of the network, which is higher for the easier problems
Ultrasmall volume Plasmons - yet with complete retardation effects
Nano particle-plasmons are attributed to quasi-static oscillation with no
wave propagation due to their subwavelength size. However, when located within
a band-gap medium (even in air if the particle is small enough), the particle
interfaces are acting as wave-mirrors, incurring small negative retardation.
The latter when compensated by a respective (short) propagation within the
particle substantiates a full-fledged resonator based on constructive
interference. This unusual wave interference in the deep subwavelength regime
(modal-volume<0.001lambda^3) significantly enhances the Q-factor, e.g. 50
compared to the quasi-static limit of 5.5.Comment: 16 pages, 6 figure
Tunneling Spectroscopy of Disordered Two-Dimensional Electron Gas in the Quantum Hall Regime
Recently, Dial et al. presented measurements of the tunneling density of
states into the bulk of a two dimensional electron gas under strong magnetic
fields. Several high energy features appear in the measured spectrum showing a
distinct dependence on filling factor and a unique response to temperature. We
present a quantitative account of the observed structure, and argue it results
from the repulsive Coulomb interactions between the tunneling electron and
states localized at disorder potential wells. The quenching of the kinetic
energy by the applied magnetic field leads to an electron addition spectrum
that is primarily determined by the external magnetic field and is nearly
independent of the disorder potential. Using a Hartree-Fock model we reproduce
the salient features of the observed structure
Vibrational inelastic scattering effects in molecular electronics
We describe how to treat the interaction of travelling electrons with
localised vibrational modes in nanojunctions. We present a multichannel
scattering technique which can be applied to calculate the transport properties
for realistic systems, and show how it is related to other methods that are
useful in particular cases. We apply our technique to describe recent
experiments on the conductance through molecular junctions.Comment: LaTeX, 12 pages, 3 figure
The Effects of Resonant Tunneling on Magnetoresistance through a Q uantum Dot
The effect of resonant tunneling on magnetoresistance (MR) is studied
theoretically in a double junction system. We have found that the ratio of the
MR of the resonant peak current is reduced more than that of the single
junction, whereas that of the valley current is enhanced depending on the
change of the discrete energy-level under the change of magnetic field. We also
found that the peak current-valley current (PV) ratio decreases when the
junction conductance increases.Comment: 11 pages, 3 figures(mail if you need), use revtex.st
Hereditarily finite sets and identity trees
AbstractSome asymptotic results about the sizes of certain sets of hereditarily finite sets, identity trees, and finite games are proven
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