scholarly journals Decoherent Excitation of Transverse Free Currents in Dielectric Liquids via Inter-Molecular Interactions

2021 ◽  
Vol 9 ◽  
Author(s):  
C. S. DiLoreto ◽  
C. Rangan
Keyword(s):  
Short Duration ◽  
Incident Light ◽  
Optical Scattering ◽  
Lower Field ◽  
Electromagnetic Pulses ◽  
Dielectric Liquids ◽  
Dipole Interactions ◽  
Linearly Polarized ◽  
Two Level Systems ◽  
Dense Cluster

We present a theoretical model for a class of optical scattering experiments in which short-duration, linearly-polarized electromagnetic pulses scatter off dielectric liquids. The pattern of scattering, particularly in the transverse direction, indicates that significant free currents are generated in the direction orthogonal to the polarization of the incident light. Modelling the target as a dense cluster of two-level systems, we show that transverse free currents are produced by short duration, electric-dipole interactions between proximate molecules, and result in scattering patterns similar to those observed in the experiments. Calculations provide a rationale for why these scattering patterns are not observed in the same molecules at lower densities or with lower field intensities. These features make this model a relevant alternative to proposed transverse optical magnetism theories.

scholarly journals Formation of half-period surface relief gratings in azobenzene containing polymer films

2020 ◽  
Vol 126 (9) ◽  
Author(s):  
Joachim Jelken ◽  
Carsten Henkel ◽  
Svetlana Santer
Keyword(s):  
Polymer Film ◽  
Polymer Films ◽  
Surface Relief ◽  
Incident Light ◽  
Glassy State ◽  
Polarized Light ◽  
Half Period ◽  
Polarization Distribution ◽  
Linearly Polarized ◽  
Set Up

Abstract We study the peculiar response of photo-sensitive polymer films irradiated with a certain type of interference pattern where one interfering beam is S-polarized, while the second one is P-polarized. The polymer film, although in a glassy state, deforms following the local polarization distribution of the incident light, and a surface relief grating (SRG) appears whose period is half the optical one. All other types of interference patterns result in the matching of both periods. The topographical response is triggered by the alignment of photo-responsive azobenzene containing polymer side chains orthogonal to the local electrical field, resulting in a bulk birefringence grating (BBG). We investigate the process of dual grating formation (SRG and BBG) in a polymer film utilizing a dedicated set-up that combines probe beam diffraction and atomic force microscopy (AFM) measurements, and permits acquiring in situ and in real-time information about changes in local topography and birefringence. We find that the SRG maxima appear at the positions of linearly polarized light (tilted by 45° relative to the grating vector), causing the formation of the half-period topography. This permits to inscribe symmetric and asymmetric topography gratings with sub-wavelength period, while changing only slightly the polarization of one of the interfering beams. We demonstrate an easy generation of sawtooth profiles (blazed gratings) with adjustable shape. With these results, we have taken a significant step in understanding the photo-induced deformation of azo-polymer films.

The Effect of Short-duration, High-intensity Electromagnetic Pulses on Fresh Ulnar Fractures in Rats

2002 ◽  
Vol 49 (1) ◽  
pp. 33-37 ◽  
Author(s):  
S. LEISNER ◽  
R. SHAHAR ◽  
I. AIZENBERG ◽  
D. LICHOVSKY ◽  
T. LEVIN-HARRUS
Keyword(s):  
Short Duration ◽  
High Intensity ◽  
Electromagnetic Pulses

Formation and emission of intense electromagnetic pulses by means of an insulated rod antenna excited by a short-duration high-current relativistic electron beam

2000 ◽  
Vol 26 (4) ◽  
pp. 360-362 ◽  
Author(s):  
N. I. Gaponenko ◽  
A. M. Gorban’ ◽  
D. V. Gorozhanin ◽  
V. I. Kurilko ◽  
S. M. Latinskii ◽  
...  
Keyword(s):  
Electron Beam ◽  
Relativistic Electron ◽  
Short Duration ◽  
Relativistic Electron Beam ◽  
High Current ◽  
Electromagnetic Pulses

Visual pigments and dichroism of anchovy cones: A model system for polarization detection.

2002 ◽  
Vol 19 (4) ◽  
pp. 467-473 ◽  
Author(s):  
IÑIGO NOVALES FLAMARIQUE ◽  
FERENC I. HÁROSI
Keyword(s):  
Detection System ◽  
Incident Light ◽  
Polarized Light ◽  
Visual Pigments ◽  
Rods And Cones ◽  
Lamellar Orientation ◽  
Cone System ◽  
Linearly Polarized ◽  
Bay Anchovy ◽  
Polarization Detection

The retinas of anchovies have two unique photoreceptor types: “bifid” and “long” cones (Fineran & Nicol, 1976). The outer segments of these cells contain multiple layers of membranes (lamellae) oriented longitudinally (axially). This orientation is distinct from that in all other vertebrate rods and cones, where the lamellae are stacked transversely with their planes perpendicular to the incident light path. Although the common arrangement provides optimal absorption for normally incident light rays, it is also insensitive to the rays' direction of vibration (i.e. their polarization). In contrast, the two mutually perpendicular sets of axially oriented lamellae segregated into bifid and long cones could function as the principal analyzers for linearly polarized light, as previously hypothesized (Fineran & Nicol, 1976, 1978). Here, we report on a microspectrophotometric study that shows (1) the presence of two spectrally distinct visual pigments in the three photoreceptor types of the bay anchovy retina; these are typical vertebrate pigments in that they bleach, when exposed to light, and have absorption spectra like all other vitamin A1-based visual pigments; (2) that the rods and cones exhibit dichroic absorption of light in accordance with their lamellar orientation, and (3) that the two cone types of the retina contain a spectrally indistinguishable pigment with peak absorbance (λmax) around 540 nm, while the rods contain a rhodopsin-like pigment with λmax near 500 nm. Compared to other vertebrates, anchovies are remarkable for using a monochromatic cone system with unusual specializations supportive of a polarization detection system.

Obtaining Circularly Polarized Optical Spots Beyond the Diffraction Limit Using Plasmonic Nano-Antennas

2009 ◽  
Vol 1208 ◽  
Author(s):  
Erdem Ogut ◽  
Gullu Kiziltas ◽  
Kursat Sendur
Keyword(s):  
Incident Light ◽  
Near Field ◽  
Diffraction Limit ◽  
Polarization Angle ◽  
Circularly Polarized ◽  
All Optical ◽  
Linearly Polarized ◽  
Linearly Polarized Radiation ◽  
Optical Applications ◽  
Polarized Radiation

AbstractWith advances in nanotechnology, emerging plasmonic nano-optical applications, such as all-optical magnetic recording, require circularly-polarized electromagnetic radiation beyond the diffraction limit. In this study, a plasmonic cross-dipole nano-antenna is investigated to obtain a circularly polarized near-field optical spot with a size smaller than the diffraction limit of light. The performance of the nano-antenna is investigated through numerical simulations. In the first part of this study, the nano-antenna is illuminated with a diffraction-limited circularly-polarized radiation to obtain circularly polarized optical spots at nanoscale. In the second part, diffraction limited linearly polarized radiation is used. An optimal configuration for the nano-antenna and the polarization angle of the incident light is identified to obtain a circularly polarized optical spot beyond the diffraction limit from a linearly polarized diffraction limited radiation.

Polarization Aspects of Localized Optical Spots Obtained Using Plasmonic Nano-Antennas

2010 ◽  
Vol 1248 ◽  
Author(s):  
Erdem Ogut ◽  
Kursat Sendur
Keyword(s):  
Electromagnetic Radiation ◽  
Incident Light ◽  
Diffraction Limit ◽  
Stokes Parameters ◽  
Polarization Angle ◽  
All Optical ◽  
Linearly Polarized ◽  
Linearly Polarized Radiation ◽  
Elliptically Polarized ◽  
Polarized Radiation

AbstractElectromagnetic radiation beyond the diffraction limit with a particular polarization emerges as a need for plasmonic applications. One of these applications is all-optical magnetic recording, which requires circularly-polarized electromagnetic radiation. In this study, a plasmonic cross-dipole nano-antenna is illuminated with diffraction-limited linearly polarized radiation. An optimal configuration for the nano-antenna and the polarization angle of the incident light is identified to obtain linearly, circularly, and elliptically polarized optical spots beyond the diffraction limit. The Poincaré sphere representation is utilized to visually present calculated Stokes parameters for optical spots with linear, circular, and elliptical polarizations from specific antenna geometries.

scholarly journals Orientation of Chiral Schiff Base Metal Complexes Involving Azo-Groups for Induced CD on Gold Nanoparticles by Polarized UV Light Irradiation

Symmetry ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1094
Author(s):  
Nobumitsu Sunaga ◽  
Tomoyuki Haraguchi ◽  
Takashiro Akitsu
Keyword(s):  
Gold Nanoparticles ◽  
Schiff Base ◽  
Uv Light ◽  
Light Irradiation ◽  
Spatial Features ◽  
Dipole Interactions ◽  
Uv Light Irradiation ◽  
Linearly Polarized ◽  
Chiral Species ◽  
Schiff Base Metal Complexes

In this study, we report the synthesis, characterization, and chiroptical properties of azo-group-containing chiral salen type Schiff base Ni(II), Cu(II), and Zn(II) complexes absorbed on gold nanoparticles (AuNPs) of 10 nm diameters. Induced circular dichroism (CD) around the plasmon region from the chiral species weakly adsorbed on the surface of AuNP were observed when there were appropriate dipole–dipole interactions at the initial states. Spectral changes were also observed by not only cis-trans photoisomerization of azo-groups but also changes of orientation due to Weigert effect of azo-dyes after linearly polarized UV light irradiation. Spatial features were discussed based on dipole-dipole interactions mainly within an exciton framework.

scholarly journals Intrinsic optical and passive electrical properties of cut frog twitch fibers.

1987 ◽  
Vol 89 (1) ◽  
pp. 1-40 ◽  
Author(s):  
M Irving ◽  
J Maylie ◽  
N L Sizto ◽  
W K Chandler
Keyword(s):  
Time Course ◽  
Internal State ◽  
Incident Light ◽  
Operation Mode ◽  
Optical Measurements ◽  
Fiber Axis ◽  
Simple Method ◽  
General Physiology ◽  
Linearly Polarized ◽  
The Individual

This article describes a new apparatus for making simultaneous optical measurements on single muscle fibers at three different wavelengths and two planes of linear polarization. There are two modes of operation: mode 1 measures the individual absorbances of light linearly polarized along and perpendicular to the fiber axis, and mode 2 measures retardation (or birefringence) and the average of the two absorbance components. Although some intact frog twitch fibers were studied, most experiments used cut fibers (Hille, B., and D. T. Campbell. 1976. Journal of General Physiology. 67:265-293) mounted in a double-Vaseline-gap chamber (Kovacs, L., E. Rios, and M. F. Schneider. 1983. Journal of Physiology. 343:161-196). The end-pool segments were usually exposed for 2 min to 0.01% saponin. This procedure, used in subsequent experiments to make the external membranes in the end pools permeable to Ca indicators (Maylie, J., M. Irving, N. L. Sizto, G. Boyarsky, and W. K. Chandler. 1987. Journal of General Physiology. 89:145-176; Maylie, J., M. Irving, N. L. Sizto, and W. K. Chandler. 1987. Journal of General Physiology. 89:41-143), was routinely employed so that all our cut fiber results would be comparable. A simple method, which does not require microelectrodes, allowed continual estimation of a fiber's membrane (rm) and internal longitudinal (ri) resistances as well as the external resistance (re) under the Vaseline seals. The values of rm and ri obtained from cut fibers with this method agree reasonably well with values obtained from intact fibers using microelectrode techniques. Optical measurements were made on resting and action potential-stimulated fibers. The intrinsic fiber absorbance, defined operationally as log10 of the ratio of incident light to transmitted light intensity, was similar in intact and cut preparations, as were the changes that accompanied stimulation. On the other hand, the resting birefringence and the peak of the active change in cut fibers were, respectively, only 0.8 and 0.7 times the corresponding values in intact fibers. Both the amplitude and the half-width of the active retardation signal increased considerably during the time course of cut fiber experiments; a twofold increase in 2 h was not unusual. Such changes are probably due to a progressive alteration in the internal state of the cut fibers.

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