15,451 research outputs found
Low frequency creep in CoNiFe films
The results of an investigation of domain wall motion excited by slow rise-time, bipolar, hard-axis pulses in vacuum deposited CoNiFe films 1500A to 2000A thick are presented. The results are consistent with those of comparable NiFe films in spite of large differences in film properties. The present low frequency creep data together with previously published results in this and other laboratories can be accounted for by a model which requires that the wall structure change usually associated with low frequency creep be predominately a gyromagnetic process. The correctness of this model is reinforced by the observation that the wall coercive force, the planar wall mobility, and the occurrence of an abrupt wall structure change are the only properties closely correlated to the creep displacement characteristics of a planar wall in low dispersion films
Giant Modal Gain, Amplified Surface Plasmon Polariton Propagation, and Slowing Down of Energy Velocity in a Metal-Semiconductor-Metal Structure
We investigated surface plasmon polariton (SPP) propagation in a
metal-semiconductor-metal structure where semiconductor is highly excited to
have optical gain. We show that near the SPP resonance, the imaginary part of
the propagation wavevector changes from positive to hugely negative,
corresponding to an amplified SPP propagation. The SPP experiences a giant gain
that is 1000 times of material gain in the excited semiconductor. We show that
such a giant gain is related to the slowing down of average energy propagation
in the structur
eHealth interventions for people with chronic kidney disease
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: This review aims to look at the benefits and harms of using eHealth interventions in the CKD population
Multiplpe Choice Minority Game With Different Publicly Known Histories
In the standard Minority Game, players use historical minority choices as the
sole public information to pick one out of the two alternatives. However,
publishing historical minority choices is not the only way to present global
system information to players when more than two alternatives are available.
Thus, it is instructive to study the dynamics and cooperative behaviors of this
extended game as a function of the global information provided. We numerically
find that although the system dynamics depends on the kind of public
information given to the players, the degree of cooperation follows the same
trend as that of the standard Minority Game. We also explain most of our
findings by the crowd-anticrowd theory.Comment: Extensively revised, to appear in New J Phys, 7 pages with 4 figure
Recombination Statistics For Neutron Bombarded Silicon Transistors
This paper presents a recombination statistical model for the neutron-induced base current component reported previously. The derivation was based on the following: 1) the current equation for the induced current component developed previously; 2) the Shockley-Read-Hall statistics for holes and electrons; and 3) the recombination statistics derived by Sah, Noyce and Shockley for sites in the bulk space-charge region. The recombination statistics model depends on the diffusion potential, the junction voltage, the activation energy, temperature, and the ratio of capture cross-sections for holes and electrons. The utility of such a recombination statistical model is illustrated by using measured parameters to predict the neutron-induced base current for p-n junction transistors and by comparing the results with measured base currents. Further, the temperature variation of the reciprocal slope term is calculated from the model and found to agree well with experiment. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc
Correlations, fluctuations and stability of a finite-size network of coupled oscillators
The incoherent state of the Kuramoto model of coupled oscillators exhibits
marginal modes in mean field theory. We demonstrate that corrections due to
finite size effects render these modes stable in the subcritical case, i.e.
when the population is not synchronous. This demonstration is facilitated by
the construction of a non-equilibrium statistical field theoretic formulation
of a generic model of coupled oscillators. This theory is consistent with
previous results. In the all-to-all case, the fluctuations in this theory are
due completely to finite size corrections, which can be calculated in an
expansion in 1/N, where N is the number of oscillators. The N -> infinity limit
of this theory is what is traditionally called mean field theory for the
Kuramoto model.Comment: 25 pages (2 column), 12 figures, modifications for resubmissio
The derived category of surface algebras: the case of the torus with one boundary component
In this paper we refine the main result of a previous paper of the author
with Grimeland on derived invariants of surface algebras. We restrict to the
case where the surface is a torus with one boundary component and give an
easily computable derived invariant for such surface algebras. This result
permits to give answers to open questions on gentle algebras: it provides
examples of gentle algebras with the same AG-invariant (in the sense of
Avella-Alaminos and Geiss) that are not derived equivalent and gives a partial
positive answer to a conjecture due to Bobi\'nski and Malicki on gentle
-cycles algebras.Comment: 22 pages, a mistake concerning the computation of the mapping class
group has been fixed, version 3: 25 pages, to appear in Algebras and
Representation Theor
On the Numerical Approximations of an Optimal Correction Problem
The numerical solution of an optimal correction problem for a damped random linear oscillator is studied. A numerical algorithm for the discretized system of the associated dynamic programming equation is given. To initiate the computation, we adopt a numerical scheme derived from the deterministic version of the problem. Next, a correction-type algorithm based on a discrete maximum principle is introduced to ensure the convergence of the iteration procedure
Comment on ``A new efficient method for calculating perturbative energies using functions which are not square integrable'': regularization and justification
The method recently proposed by Skala and Cizek for calculating perturbation
energies in a strict sense is ambiguous because it is expressed as a ratio of
two quantities which are separately divergent. Even though this ratio comes out
finite and gives the correct perturbation energies, the calculational process
must be regularized to be justified. We examine one possible method of
regularization and show that the proposed method gives traditional quantum
mechanics results.Comment: 6 pages in REVTeX, no figure
Charge sensing in carbon nanotube quantum dots on microsecond timescales
We report fast, simultaneous charge sensing and transport measurements of
gate-defined carbon nanotube quantum dots. Aluminum radio frequency single
electron transistors (rf-SETs) capacitively coupled to the nanotube dot provide
single-electron charge sensing on microsecond timescales. Simultaneously, rf
reflectometry allows fast measurement of transport through the nanotube dot.
Charge stability diagrams for the nanotube dot in the Coulomb blockade regime
show extended Coulomb diamonds into the high-bias regime, as well as even-odd
filling effects, revealed in charge sensing data.Comment: 4 pages, 4 figure
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