5,218 research outputs found
Quadrupole Interaction of Non-diffracting Beams with Two-Level Atoms
Recently it has been shown that the quadrupole interactions can be improved
significantly as the atom interacts at near resonance with the
Laguerre-Gaussian (LG) mode. In this paper, we illustrate that other kinds of
optical vortex can be also led to a considerable enhancement of quadrupole
interaction when the atom interacts with optical modes at near resonance. The
calculations are performed on an interesting situation with Cs atom, where the
process is concerned with dipole-forbidden and quadrupole-allowed transitions
with a convenable choice of atomic and optical mode parameters. In this
direction, we show that the quadrupole transitions can be significantly
enhanced and therefore they can play an interesting role and lead to new
features of atom-light interaction, which can have some constructive
implications in experiments.Comment: 9 pages, 10 figure
SOM-based algorithms for qualitative variables
It is well known that the SOM algorithm achieves a clustering of data which
can be interpreted as an extension of Principal Component Analysis, because of
its topology-preserving property. But the SOM algorithm can only process
real-valued data. In previous papers, we have proposed several methods based on
the SOM algorithm to analyze categorical data, which is the case in survey
data. In this paper, we present these methods in a unified manner. The first
one (Kohonen Multiple Correspondence Analysis, KMCA) deals only with the
modalities, while the two others (Kohonen Multiple Correspondence Analysis with
individuals, KMCA\_ind, Kohonen algorithm on DISJonctive table, KDISJ) can take
into account the individuals, and the modalities simultaneously.Comment: Special Issue apr\`{e}s WSOM 03 \`{a} Kitakiush
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