Dielectric structure

For waveguide modes in a pure dielectric structure, Nm is nmax = Max c, ns at dF = (/cutoff and nF at dF > oo. The so-called cut off thickness, (/cutoff is defined as the film thickness at which the field s propagation angle in the film gets... 

Smyth, C. P. Dielectric Structure and Behavior. New York McGraw-Hill 1955... 

It might be that the substrate-dependent broading testifies of a different anchoring of the polymer on the substrate, what could induce a different film structure, and thus a different chemistry when metallic atoms are evaporated onto the polymer. Some dielectric- structural-chemistry interrelations could explain the data presented above. Again, this will be the subject of further research. 

Table 8). This permits the interpretation of experimental data by using the electro-optical properties of flexible-chain polymers in terms of a worm-like chain model However, EB in solutions of polyelectrolytes is of a complex nature. The high value of the observed effect is caused by the polarization of the ionic atmosphere surrounding the ionized macromolecule rather than by the dipolar and dielectric structure of the polymer chain. This polarization induced by the electric field depends on the ionic state of the solution and the ionogenic properties of the polymer chain whereas its dependence on the chain structure and conformation is slight. Hence, the information on the optical, dipolar and conformational properties of macromoiecules obtained by using EB data in solutions of flexible-chain polyelectrolytes is usually only qualitative. Studies of the kinetics of the Kerr effect in polyelectrolytes (arried out by pulsed technique) are more useful since in these... 

These results reveal that- a plastic foam structure may be considered as a system of thin films and, therefore, support a model of plastic foam morphology namely a matrix system composed of thin polymeric films defining two groups of cells (macro- and microcells). Additional support in favor of this model of plastic foam structure is provided by the studies on the electric properties of plastic foams Among the numerous equations so far advanced for the calculation of the dielectric properties, the expressions which describe the dry foam structure by one of the limiting cases of a matrix system, namely a laminated dielectric structure with layers parallel to the force lines of the electrical field, agree best with the experiments >. 

The nanometer-sized single molecule can be regarded as a local probe of electromagnetic and electrostatic interactions extremely close to the molecule, because the probability of excitation depends upon the local optical field as described above. In addition, under certain conditions, the molecule s emission can be influenced by the proximity of nanoscale metallic or dielectric structures. 

For a molecule emitting within a complex dielectric structure, the radiative rate can be strongly modified relative to the rate in an infinite isotropic medium. 

A simple example of this is the case of a molecule (modeled as an oscillating dipole) close to a perfect mirror. If the dipole is parallel to the mirror, destructive interference between directly emitted light and reflected light causes a reduction in the radiative rate. In the presence of competing nonradiative decay processes, this leads to a reduction in the efficiency of emission. The variation of radiative rate with position and orientation for a molecule within an arbitrary planar dielectric structure has been modeled by Crawford.81 This model has been applied to polymer LEDs by Burns et al.,82 and Becker et al.,83 who predict significant variations in the efficiency of radiative decay in polymer LEDs depending on the distribution of exciton generation within the device. 

The dielectric, structural, relaxation time is related to the linear regime. It reflects the evolution of the average permanent dipole moment, linked to the given molecule. The dielectric relaxation time detects heterogeneities indirectly, via changes of the average surrounding of a molecule. It was shown in ref. that dielectric relaxation can be well portrayed, with small distortion only close to Tp, by the MCT critical-like dependence ... 

Liehr, Integrated processing of MOS gate dielectric structures, IEEE Transaction Semiconductor Manufacturing 7(1),... 

Surface treatment has also been used to modify the threshold voltage as well as measured mobility in pentacene and Cgo TFTs [60]. These transistors have a heavily doped silicon/silicon oxide gate dielectric structure where alkyl, aUcylamine, and fluoroalkyl silanes are used to modify the Si02. Evaporated pentacene and Cgo form the active p- and n-type semiconductors. The experimental effect of these monolayer treatments is to alter Vj and effective mobility dramatically (see Table 3.2.3). For pentacene, the mobility decreases from -F, -CH3, untreated, -NH2, with a similar shift in Vj from 17 to -11V. The opposite trend is observed for Cgo, in which mobility is largest for the untreated material and smallest for the fluorinated SAM. In the case of Vji the alkylamine SAM shows the lowest VjOi 5.3 V. The underlying reasons for these trends are not completely understood. What is intriguing is how dramatic... 

Figure 1. A three-layer periodical dielectric structure.

Figure 1. Stepwise potential profile U(x) for an electron and the relevant refraction index profile n(x) inherent in a complex dielectric structure.

HIGH-FIELD ANODIZATION TO FORM NANOSIZED PORE DIELECTRIC STRUCTURES... 

Bold faced items in Table 1 distinguish the parameters for the high field anodizing mode which was especially developed at to obtain nanoporous aluminium oxide with large D/d ratio. The italics show the literature data, the other data show results obtained in our experiments. Based on the experimental results, the techniques have been designed for fabrication regular nanosized magnetic-anodic dielectric structures. 

The demonstrated method is readily applicable to other systems. The ability both to enhance QD PL/responses and to suppress analyte adsorption induced wetting effects through utilization of porous structures is essential for these fluorescence-based sensors. Refined design of the platform through a creation of ordered periodic dielectric structures of desired dimensions, together with optical amplifications by surface plasmon resonance of noble metal nanoparticles, may further contribute to the sensor development. Overall this would offer benefits for employing QDs in a broader range of device applications. 

It has been proposed that sub-wavelength dielectric structures alter the effective medium without affecting the diffraction pattern in an optical system [35]. An expansion of the effective medium approach was also suggested for metals [36]. 

Differential Energy Control and the Dielectric Structure of Cells... 

Determination of Dielectric Structure of Cells by Inversion of Their Raman Spectra... 

Differential Energy Control and Dielectric Structure 5. Discussion of Results... 

The results show that for cases consistent with the Raman spectral response for cells 48 hr after infection in Webb s experiments, there is a maximum energy transfer J (line intensity) rf(l/A) to the cell membrane at approximately 45, 90, 140, and 180 cm This does not appear to be so for the normal cell, where lower levels of energy transfer seem associated with normal behavior. The dielectric structure of layers calculated for normal cells does not affect the shape or frequency of the Raman lines observed for the normal cell. (The dielectric layer model used cannot account for the splitting of lines seen in the spectra of tumor cells.Such splitting is of great importance in terms of the possible degeneracy in the oscillatory modes of molecules—perhaps from breaks in the fibronectin layer.)... 

R. G. Ashcroft, H. G. L. Coster, and J. R. Smith, The Molecular Organization of Bimolecular Lipid Membranes. The Dielectric Structure of the Hydrophilic/Hydrophobic Interface, Biochim. Biophys. Acta 643, 191-204 (1981). 

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