106,431 research outputs found
Ytterbium- and chromium-doped fibre laser: from chaotic self-pulsing to passive Q-switching
A spontaneously chaotic, self-pulsing ytterbium-doped fibre laser is
partially stabilized into the passively Q-switched mode of operation using a
chromium-doped saturable absorber fibre. This original all-fibre laser produces
sustained and stable trains of smooth pulses at high repetition rate.Comment: 1 page abstract; at 20th International laser physics workshop,
Sarajevo : Bosnia And Herzegovina (2011
Imbedding estimates and elliptic equations with discontinuous coefficients in unbounded domains
In this paper we deal with the multiplication operator u ∈ W^{k,p} (Ω) → gu ∈ L^q (Ω), with g belonging to a space of Morrey type. We apply our results in order to establish an a-priori bound for the solutions of the Dirichlet problem concerning elliptic equations with discontinuous coefficients
Complete set of invariants for a Bykov attractor
In this paper we consider an attracting heteroclinic cycle made by a
1-dimensional and a 2-dimensional separatrices between two hyperbolic saddles
having complex eigenvalues. The basin of the global attractor exhibits historic
behaviour and, from the asymptotic properties of these non-converging time
averages, we obtain a complete set of invariants under topological conjugacy in
a neighborhood of the cycle. These invariants are determined by the quotient of
the real parts of the eigenvalues of the equilibria, a linear combination of
their imaginary components and also the transition maps between two cross
sections on the separatrices.Comment: 23 pages, 4 figure
Matched filter for multi-transducers resonant GW antennas
We analyze two kinds of matched filters for data output of a spherical
resonant GW detector. In order to filter the data of a real sphere, a strategy
is proposed, firstly using an omnidirectional in-line filter, which is supposed
to select periodograms with excitations, secondly by performing a directional
filter on such selected periodograms, finding the wave arrival time, direction
and polarization. We point out that, as the analytical simplifications
occurring in the ideal 6 transducers TIGA sphere do not hold for a real sphere,
using a 5 transducers configuration could be a more convenient choice.Comment: 15 pages and 4 figures, version accepted for publication in PR
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