7,707 research outputs found
Statistics of Chaotic Resonances in an Optical Microcavity
Distributions of eigenmodes are widely concerned in both bounded and open
systems. In the realm of chaos, counting resonances can characterize the
underlying dynamics (regular vs. chaotic), and is often instrumental to
identify classical-to-quantum correspondence. Here, we study, both
theoretically and experimentally, the statistics of chaotic resonances in an
optical microcavity with a mixed phase space of both regular and chaotic
dynamics. Information on the number of chaotic modes is extracted by counting
regular modes, which couple to the former via dynamical tunneling. The
experimental data are in agreement with a known semiclassical prediction for
the dependence of the number of chaotic resonances on the number of open
channels, while they deviate significantly from a purely
random-matrix-theory-based treatment, in general. We ascribe this result to the
ballistic decay of the rays, which occurs within Ehrenfest time, and
importantly, within the timescale of transient chaos. The present approach may
provide a general tool for the statistical analysis of chaotic resonances in
open systems.Comment: 5 pages, 5 figures, and a supplemental informatio
Influence of unsymmetrical periodicity on extraordinary transmission through periodic arrays of subwavelength holes
Quadrate hole array is explored to study the influence of unsymmetrical
periodicity on extraordinary optical transmission through periodic arrays of
subwavelength holes. It is found that the transmission efficiency of light and
the ratio between transmission efficiencies of horizontal and vertical
polarized light can be continuously tuned by rotating the quadrate hole array.
We can calculate out the transmission spectra (including the heights and
locations of peaks) for any rotation angle with a simple theoretical
model.Comment: 6 pages, 5 figure
2-(Carboxymethylsulfanyl)pyridine-3-carboxylic acid monohydrate
The title compound, C8H7NO4S·H2O, was obtained by reaction of 2-mercaptopyridine-3-carboxylic acid with chloroacetic acid. In the molecular structure, the dihedral angle between the two least-squares planes defined by the pyridine ring and the carboxy group is 8.32 (9)°. The carboxymethylsulfanyl group makes a torsion angle of 82.64 (12)° with the pyridine ring. An intramolecular O—H⋯N hydrogen bond between the acidic function of the carboxymethylsulfanyl group and the pyridine N atom stabilizes the conformation, whereas intermolecular O—H⋯O hydrogen bonding with the uncoordinated water molecules is responsible for packing of the structure, leading to chains propagating in [001]
A closer look at interacting dark energy with statefinder hierarchy and growth rate of structure
We investigate the interacting dark energy models by using the diagnostics of
statefinder hierarchy and growth rate of structure. We wish to explore the
deviations from CDM and to differentiate possible degeneracies in the
interacting dark energy models with the geometrical and structure growth
diagnostics. We consider two interacting forms for the models, i.e., and , with being the dimensionless
coupling parameter. Our focus is the ICDM model that is a
one-parameter extension to CDM by considering a direct coupling
between the vacuum energy () and cold dark matter (CDM), with the only
additional parameter . But we begin with a more general case by
considering the ICDM model in which dark energy has a constant
(equation-of-state parameter). For calculating the growth rate of structure, we
employ the "parametrized post-Friedmann" theoretical framework for interacting
dark energy to numerically obtain the values for the models. We
show that in both geometrical and structural diagnostics the impact of is
much stronger than that of in the ICDM model. We thus wish to have a
closer look at the ICDM model by combining the geometrical and
structural diagnostics. We find that the evolutionary trajectories in the
-- plane exhibit distinctive features and the departures
from CDM could be well evaluated, theoretically, indicating that the
composite null diagnostic is a promising tool for
investigating the interacting dark energy models.Comment: 17 pages, 4 figures; accepted for publication in JCA
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