157 research outputs found
Optical bistability in a -type atomic system including near dipole-dipole interaction
The advantage of optical bistability (OB) using three-level
electromagnetically induced transparency (EIT) atomic system over the two-level
system is its controllability, as absorption, dispersion, and optical
nonlinearity in one of the atomic transitions can be modified considerably by
the field interacting with nearby atomic transitions. This is due to induced
atomic coherences generated in such EIT system. The inclusion of near
dipole-dipole (NDD) interaction among atoms further modifies absorption,
dispersion, and optical nonlinearity of three-level EIT system and the OB can
also be controlled by this interaction, producing OB to multistability.Comment: 15 pages, 6 figure
Refractive index of a transparent liquid measured with a concave mirror
This paper describes the spherical concave mirror method for measuring the
index of refraction of transparent liquids. We derived the refractive index
equation using Snell's law and the small-angle approximation. We also verified
the validity of this method using the traditional spherical mirror and
thin-lens Gaussian equations.Comment: IOPart, 8 pages, 4 figure
Visualizing the logistic map with a microcontroller
The logistic map is one of the simplest nonlinear dynamical systems that
clearly exhibit the route to chaos. In this paper, we explored the evolution of
the logistic map using an open-source microcontroller connected to an array of
light emitting diodes (LEDs). We divided the one-dimensional interval
into ten equal parts, and associated and LED to each segment. Every time an
iteration took place a corresponding LED turned on indicating the value
returned by the logistic map. By changing some initial conditions of the
system, we observed the transition from order to chaos exhibited by the map.Comment: LaTeX, 6 pages, 3 figures, 1 listin
Cavity Quantum Electrodynamics of a two-level atom with modulated fields
We studied the interaction of a two-level atom with a frequency modulated
cavity mode in an ideal optical cavity. The system, described by a
Jaynes-Cumming Hamiltonian, gave rise to a set of stiff nonlinear first order
equations solved numerically using implicit and semi-implicit numerical
algorithms. We explored the evolution of the atomic system using nonlinear
dynamics tools, like time series, phase plane, power spectral density, and
Poincar\'{e} sections plots, for monochromatic and bichromatic modulations of
the cavity field. The system showed quasiperiodic and possibly chaotic behavior
when the selected monochromatic frequencies, or ratio of the bichromatic
frequencies were irrational (incommensurate) numbers. In addition, when the
modulated frequencies were overtones of the Rabi frequency of the system, a
single dominant frequency emerged for the system.Comment: REVTeX, 6 pages, 6 figure
An Unusual Case of Locally Advanced Glycogen-Rich Clear Cell Carcinoma of the Breast
Glycogen-rich clear cell (GRCC) is a rare subtype of breast carcinoma characterized by carcinoma cells containing an optically clear cytoplasm and intracytoplasmic glycogen. We present the case of a 55-year-old woman with a palpable mass in the right breast and clinical signs of locally advanced breast cancer (LABC). The diagnosis of GRCC carcinoma was based on certain histopathological characteristics of the tumor and immunohistochemical analysis. To our knowledge, this is the first case of GRCC LABC with intratumoral calcifications. There is no evidence of recurrence or metastatic disease after 14 months’ follow-up
Diseño metodológico de un sistema de medición del desempeño para la cadena de suministros de astilleros en Colombia
The design of a performance measurement system for the Colombian shipyard supply chain is shown in this paper, using a model that integrates the principles of the Balanced Scorecard with the fuzzy sets theory to treat uncertainty associated with selected logistics indicators, enabling better supply chain management.El presente artĂculo muestra el diseño de un sistema de mediciĂłn del desempeño para la cadena de suministros de los astilleros colombianos, usando un modelo que integra los principios del Balanced Scorecard con la teorĂa de conjuntos difusos para el tratamiento de la incertidumbre asociada a los indicadores logĂsticos seleccionados, posibilitando mejor gestiĂłn de dicha cadena
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